Over the past 14 months, as the impact of the ongoing Israel-Gaza war has rippled across the globe, a faculty-led initiative has emerged to support MIT students and staff by creating a community that transcends ethnicity, religion, and political views. Named for a flower that blooms along the Israel-Gaza border, MIT-Kalaniyot began hosting weekly community lunches that typically now draw about 100 participants. These gatherings have gained the interest of other universities seeking to help students not only cope with but thrive through troubled times, with some moving to replicate MIT’s model on their own campuses.
Now, scholars at Israel’s nine state-recognized universities will be able to compete for MIT-Kalaniyot fellowships designed to allow Israel’s top researchers to come to MIT for collaboration and training, advancing research while contributing to a better understanding of their country.
The MIT-Kalaniyot Postdoctoral Fellows Program will support scholars who have recently graduated from Israeli PhD programs to continue their postdoctoral training at MIT. Meanwhile, the new MIT-Kalaniyot Sabbatical Scholars Program will provide faculty and researchers holding sabbatical-eligible appointments at Israeli research institutions with fellowships for two academic terms at MIT.
Announcement of the fellowships through the association of Israeli university presidents spawned an enthusiastic response.
“We’ve received many emails, from questions about the program to messages of gratitude. People have told us that, during a time of so much negativity, seeing such a top-tier academic program emerge feels like a breath of fresh air,” says Or Hen, the Class of 1956 Associate Professor of Physics and associate director of the Laboratory for Nuclear Science, who co-founded MIT-Kalaniyot with Ernest Fraenkel, the Grover M. Hermann Professor in Health Sciences and Technology.
Hen adds that the response from potential program donors has been positive, as well.
“People have been genuinely excited to learn about forward-thinking efforts and how they can simultaneously support both MIT and Israeli science,” he says. “We feel truly privileged to be part of this meaningful work.”
MIT-Kalaniyot is “a faculty-led initiative that emerged organically as we came to terms with some of the challenges that MIT was facing trying to keep focusing on its mission during a very difficult period for the U.S., and obviously for Israelis and Palestinians,” Fraenkel says.
As the MIT-Kalaniyot Program gained momentum, he adds, “we started talking about positive things faculty can do to help MIT fulfill its mission and then help the world, and we recognized many of the challenges could actually be helped by bringing more brilliant scholars from Israel to MIT to do great research and to humanize the face of Israelis so that people who interact with them can see them, not as some foreign entity, but as the talented person working down the hallway.”
“MIT has a long tradition of connecting scholarly communities around the world,” says MIT President Sally Kornbluth. “Programs like this demonstrate the value of bringing people and cultures together, in pursuit of new ideas and understanding.”
Open to applicants in the humanities, architecture, management, engineering, and science, both fellowship programs aim to embrace Israel’s diverse demographics by encouraging applications from all communities and minority groups throughout Israel.
Fraenkel notes that because Israeli universities reflect the diversity of the country, he expects scholars who identify as Israeli Arabs, Palestinian citizens of Israel, and others could be among the top candidates applying and ultimately selected for MIT-Kalaniyot fellowships.
MIT is also expanding its Global MIT At-Risk Fellows Program (GMAF), which began last year with recruitment of scholars from Ukraine, to bring Palestinian scholars to campus next fall. Fraenkel and Hen noted their close relationship with GMAF-Palestine director Kamal Youcef-Toumi, a professor in MIT’s Department of Mechanical Engineering.
“While the programs are independent of each other, we value collaboration at MIT and are hoping to find positive ways that we can interact with each other,” Fraenkel says.
Also growing up alongside MIT-Kalaniyot’s fellowship programs will be new Kalaniyot chapters at universities such as the University of Pennsylvania and Dartmouth College, where programs have already begun, and others where activity is starting up. MIT’s inspiration for these efforts, Hen and Fraenkel say, is a key aspect of the Kalaniyot story.
“We formed a new model of faculty-led communities,” Hen says. “As faculty, our roles typically center on teaching, mentoring, and research. After October 7 happened, we saw what was happening around campus and across the nation and realized that our roles had to expand. We had to go beyond the classroom and the lab to build deeper connections within the community that transcends traditional academic structures. This faculty-led approach has become the essence of MIT-Kalaniyot, and is now inspiring similar efforts across the nation.”
Once the programs are at scale, MIT plans to bring four MIT-Kalaniyot Postdoctoral Fellows to campus annually (for three years each), as well as four MIT-Kalaniyot Sabbatical Scholars, for a total of 16 visiting Israeli scholars at any one time.
“We also hope that when they go back, they will be able to maintain their research ties with MIT, so we plan to give seed grants to encourage collaboration after someone leaves,” Fraenkel says. “I know for a lot of our postdocs, their time at MIT is really critical for making networks, regardless of where they come from or where they go. Obviously, it’s harder when you’re across the ocean in a very challenging region, and so I think for both programs it would be great to be able to maintain those intellectual ties and collaborate beyond the term of their fellowships.”
A common thread between the new Kalaniyot programs and GMAF-Palestine, Hen says, is to rise beyond differences that have been voiced post-Oct. 7 and refocus on the Institute’s core research mission.
“We're bringing in the best scholars from the region — Jews, Israelis, Arabs, Palestinians — and normalizing interactions with them and among them through collaborative research,” Hen says. “Our mission is clear: to focus on academic excellence by bringing outstanding talent to MIT and reinforcing that we are here to advance research in service of humanity.”
Making classical music and math more accessibleIn math and in music, senior Holden Mui values interesting ideas, solving problems creatively, and finding meaning in their structures.Senior Holden Mui appreciates the details in mathematics and music. A well-written orchestral piece and a well-designed competitive math problem both require a certain flair and a well-tuned sense of how to keep an audience’s interest.
“People want fresh, new, non-recycled approaches to math and music,” he says. Mui sees his role as a guide of sorts, someone who can take his ideas for a musical composition or a math problem and share them with audiences in an engaging way. His ideas must make the transition from his mind to the page in as precise a way as possible. Details matter.
A double major in math and music from Lisle, Illinois, Mui believes it’s important to invite people into a creative process that allows a kind of conversation to occur between a piece of music he writes and his audience, for example. Or a math problem and the people who try to solve it. “Part of math’s appeal is its ability to reveal deep truths that may be hidden in simple statements,” he argues, “while contemporary classical music should be available for enjoyment by as many people as possible.”
Mui’s first experience at MIT was as a high school student in 2017. He visited as a member of a high school math competition team attending an event hosted and staged by MIT and Harvard University students. The following year, Mui met other students at math camps and began thinking seriously about what was next.
“I chose math as a major because it’s been a passion of mine since high school. My interest grew through competitions and continued to develop it through research,” he says. “I chose MIT because it boasts one of the most rigorous and accomplished mathematics departments in the country.”
Mui is also a math problem writer for the Harvard-MIT Math Tournament (HMMT) and performs with Ribotones, a club that travels to places like retirement homes or public spaces on the Institute’s campus to play music for free.
Mui studies piano with Timothy McFarland, an artist affiliate at MIT, through the MIT Emerson/Harris Fellowship Program, and previously studied with Kate Nir and Matthew Hagle of the Music Institute of Chicago. He started piano at the age of five and cites French composer Maurice Ravel as one of his major musical influences.
As a music student at MIT, Mui is involved in piano performance, chamber music, collaborative piano, the MIT Symphony Orchestra as a violist, conducting, and composition.
He enjoys the incredible variety available within MIT’s music program. “It offers everything from electronic music to world music studies,” he notes, “and has broadened my understanding and appreciation of music’s diversity.”
Collaborating to create
Throughout his academic career, Mui found himself among like-minded students like former Yale University undergraduate Andrew Wu. Together, Mui and Wu won an Emergent Ventures grant. In this collaboration, Mui wrote the music Wu would play. Wu described his experience with one of Mui’s compositions, “Poetry,” as “demanding serious focus and continued re-readings,” yielding nuances even after repeated listens.
Another of Mui’s compositions, “Landscapes,” was performed by MIT’s Symphony Orchestra in October 2024 and offered audiences opportunities to engage with the ideas he explores in his music.
One of the challenges Mui discovered early is that academic composers sometimes create music audiences might struggle to understand. “People often say that music is a universal language, but one of the most valuable insights I’ve gained at MIT is that music isn’t as universally experienced as one might think,” he says. “There are notable differences, for example, between Western music and world music.”
This, Mui says, broadened his perspective on how to approach music and encouraged him to consider his audience more closely when composing. He treats music as an opportunity to invite people into how he thinks.
Creative ideas, accessible outcomes
Mui understands the value of sharing his skills and ideas with others, crediting the MIT International Science and Technology Initiatives (MISTI) program with offering multiple opportunities for travel and teaching. “I’ve been on three MISTI trips during IAP [Independent Activities Period] to teach mathematics,” he says.
Mui says it’s important to be flexible, dynamic, and adaptable in preparation for a fulfilling professional life. Music and math both demand the development of the kinds of soft skills that can help him succeed as a musician, composer, and mathematician.
“Creating math problems is surprisingly similar to writing music,” he argues. “In both cases, the work needs to be complex enough to be interesting without becoming unapproachable.” For Mui, designing original math problems is “like trying to write down an original melody.”
“To write math problems, you have to have seen a lot of math problems before. To write music, you have to know the literature — Bach, Beethoven, Ravel, Ligeti — as diverse a group of personalities as possible.”
A future in the notes and numbers
Mui points to the professional and personal virtues of exploring different fields. “It allows me to build a more diverse network of people with unique perspectives,” he says. “Professionally, having a range of experiences and viewpoints to draw on is invaluable; the broader my knowledge and network, the more insights I can gain to succeed.”
After graduating, Mui plans to pursue doctoral study in mathematics following the completion of a cryptography internship. “The connections I’ve made at MIT, and will continue to make, are valuable because they’ll be useful regardless of the career I choose,” he says. He wants to continue researching math he finds challenging and rewarding. As with his music, he wants to strike a balance between emotion and innovation.
“I think it’s important not to pull all of one’s eggs in one basket,” he says. “One important figure that comes to mind is Isaac Newton, who split his time among three fields: physics, alchemy, and theology.” Mui’s path forward will inevitably include music and math. Whether crafting compositions or designing math problems, Mui seeks to invite others into a world where notes and numbers converge to create meaning, inspire connection, and transform understanding.
MIT welcomes Frida Polli as its next visiting innovation scholarThe neuroscientist turned entrepreneur will be hosted by the MIT Schwarzman College of Computing and focus on advancing the intersection of behavioral science and AI across MIT.Frida Polli, a neuroscientist, entrepreneur, investor, and inventor known for her leading-edge contributions at the crossroads of behavioral science and artificial intelligence, is MIT’s new visiting innovation scholar for the 2024-25 academic year. She is the first visiting innovation scholar to be housed within the MIT Schwarzman College of Computing.
Polli began her career in academic neuroscience with a focus on multimodal brain imaging related to health and disease. She was a fellow at the Psychiatric Neuroimaging Group at Mass General Brigham and Harvard Medical School. She then joined the Department of Brain and Cognitive Sciences at MIT as a postdoc, where she worked with John Gabrieli, the Grover Hermann Professor of Health Sciences and Technology and a professor of brain and cognitive sciences.
Her research has won many awards, including a Young Investigator Award from the Brain and Behavior Research Foundation. She authored over 30 peer-reviewed articles, with notable publications in the Proceedings of the National Academy of Sciences, the Journal of Neuroscience, and Brain. She transitioned from academia to entrepreneurship by completing her MBA at the Harvard Business School (HBS) as a Robert Kaplan Life Science Fellow. During this time, she also won the Life Sciences Track and the Audience Choice Award in the 2010 MIT $100K Entrepreneurship competition as a member of Aukera Therapeutics.
After HBS, Polli launched pymetrics, which harnessed advancements in cognitive science and machine learning to develop analytics-driven decision-making and performance enhancement software for the human capital sector. She holds multiple patents for the technology developed at pymetrics, which she co-founded in 2012 and led as CEO until her successful exit in 2022. Pymetrics was a World Economic Forum’s Technology Pioneer and Global Innovator, an Inc. 5000’s Fastest-Growing company, and Forbes Artificial Intelligence 50 company. Polli and pymetrics also played a pivotal role in passing the first-in-the-nation algorithmic bias law — New York’s Automated Employment Decision Tool law — which went into effect in July 2023.
Making her return to MIT as a visiting innovation scholar, Polli is collaborating closely with Sendhil Mullainathan, the Peter de Florez Professor in the departments of Electrical Engineering and Computer Science and Economics, and a principal investigator in the Laboratory for Information and Decision Systems. With Mullainathan, she is working to bring together a broad array of faculty, students, and postdocs across MIT to address concrete problems where humans and algorithms intersect, to develop a new subdomain of computer science specific to behavioral science, and to train the next generation of scientists to be bilingual in these two fields.
“Sometimes you get lucky, and sometimes you get unreasonably lucky. Frida has thrived in each of the facets we’re looking to have impact in — academia, civil society, and the marketplace. She combines a startup mentality with an abiding interest in positive social impact, while capable of ensuring the kind of intellectual rigor MIT demands. It’s an exceptionally rare combination, one we are unreasonably lucky to have,” says Mullainathan.
“People are increasingly interacting with algorithms, often with poor results, because most algorithms are not built with human interplay in mind,” says Polli. “We will focus on designing algorithms that will work synergistically with people. Only such algorithms can help us address large societal challenges in education, health care, poverty, et cetera.”
Polli was recognized as one of Inc.'s Top 100 Female Founders in 2019, followed by being named to Entrepreneur's Top 100 Powerful Women in 2020, and to the 2024 list of 100 Brilliant Women in AI Ethics. Her work has been highlighted by major outlets including The New York Times, The Wall Street Journal, The Financial Times, The Economist, Fortune, Harvard Business Review, Fast Company, Bloomberg, and Inc.
Beyond her role at pymetrics, she founded Alethia AI in 2023, an organization focused on promoting transparency in technology, and in 2024, she launched Rosalind Ventures, dedicated to investing in women founders in science and health care. She is also an advisor at the Buck Institute’s Center for Healthy Aging in Women.
"I'm delighted to welcome Dr. Polli back to MIT. As a bilingual expert in both behavioral science and AI, she is a natural fit for the college. Her entrepreneurial background makes her a terrific inaugural visiting innovation scholar,” says Dan Huttenlocher, dean of the MIT Schwarzman College of Computing and the Henry Ellis Warren Professor of Electrical Engineering and Computer Science.
New autism research projects represent a broad range of approaches to achieving a shared goalAt a symposium of the Simons Center for the Social Brain, six speakers described a diversity of recently launched studies aimed at improving understanding of the autistic brain.From studies of the connections between neurons to interactions between the nervous and immune systems to the complex ways in which people understand not just language, but also the unspoken nuances of conversation, new research projects at MIT supported by the Simons Center for the Social Brain are bringing a rich diversity of perspectives to advancing the field’s understanding of autism.
As six speakers lined up to describe their projects at a Simons Center symposium Nov. 15, MIT School of Science dean Nergis Mavalvala articulated what they were all striving for: “Ultimately, we want to seek understanding — not just the type that tells us how physiological differences in the inner workings of the brain produce differences in behavior and cognition, but also the kind of understanding that improves inclusion and quality of life for people living with autism spectrum disorders.”
Simons Center director Mriganka Sur, Newton Professor of Neuroscience in The Picower Institute for Learning and Memory and Department of Brain and Cognitive Sciences (BCS), said that even though the field still lacks mechanism-based treatments or reliable biomarkers for autism spectrum disorders, he is optimistic about the discoveries and new research MIT has been able to contribute. MIT research has led to five clinical trials so far, and he praised the potential for future discovery, for instance in the projects showcased at the symposium.
“We are, I believe, at a frontier — at a moment where a lot of basic science is coming together with the vision that we could use that science for the betterment of people,” Sur said.
The Simons Center funds that basic science research in two main ways that each encourage collaboration, Sur said: large-scale projects led by faculty members across several labs, and fellowships for postdocs who are mentored by two faculty members, thereby bringing together two labs. The symposium featured talks and panel discussions by faculty and fellows leading new research.
In a different vein, Associate Professor Ev Fedorenko of The McGovern Institute for Brain Research and BCS is leading a seven-lab collaboration aimed at understanding the cognitive and neural infrastructure that enables people to engage in conversation, which involves not only the language spoken but also facial expressions, tone of voice, and social context. Critical to this effort, she said, is going beyond previous work that studied each related brain area in isolation to understand the capability as a unified whole. A key insight, she said, is that they are all nearby each other in the lateral temporal cortex.
“Going beyond these individual components we can start asking big questions like, what are the broad organizing principles of this part of the brain?,” Fedorenko said. “Why does it have this particular arrangement of areas, and how do these work together to exchange information to create the unified percept of another individual we’re interacting with?”
While Choi and Fedorenko are looking at factors that account for differences in social behavior in autism, Picower Professor Earl K. Miller of The Picower Institute and BCS is leading a project that focuses on another phenomenon: the feeling of sensory overload that many autistic people experience. Research in Miller’s lab has shown that the brain’s ability to make predictions about sensory stimuli, which is critical to filtering out mundane signals so attention can be focused on new ones, depends on a cortex-wide coordination of the activity of millions of neurons implemented by high frequency “gamma” brain waves and lower-frequency “beta” waves. Working with animal models and human volunteers at Boston Children’s Hospital (BCH), Miller said his team is testing the idea that there may be a key difference in these brain wave dynamics in the autistic brain that could be addressed with closed-loop brain wave stimulation technology.
Simons postdoc Lukas Vogelsang, who is based in BCS Professor Pawan Sinha’s lab, is looking at potential differences in prediction between autistic and non-autistic individuals in a different way: through experiments with volunteers that aim to tease out how these differences are manifest in behavior. For instance, he’s finding that in at least one prediction task that requires participants to discern the probability of an event from provided cues, autistic people exhibit lower performance levels and undervalue the predictive significance of the cues, while non-autistic people slightly overvalue it. Vogelsang is co-advised by BCH researcher and Harvard Medical School Professor Charles Nelson.
Fundamentally, the broad-scale behaviors that emerge from coordinated brain-wide neural activity begins with the molecular details of how neurons connect with each other at circuit junctions called synapses. In her research based in The Picower Institute lab of Menicon Professor Troy Littleton, Simons postdoc Chhavi Sood is using the genetically manipulable model of the fruit fly to investigate how mutations in the autism-associated protein FMRP may alter the expression of molecular gates regulating ion exchange at the synapse , which would in turn affect how frequently and strongly a pre-synaptic neuron excites a post-synaptic one. The differences she is investigating may be a molecular mechanism underlying neural hyperexcitability in fragile X syndrome, a profound autism spectrum disorder.
In her talk, Simons postdoc Lace Riggs, based in The McGovern Institute lab of Poitras Professor of Neuroscience Guoping Feng, emphasized how many autism-associated mutations in synaptic proteins promote pathological anxiety. She described her research that is aimed at discerning where in the brain’s neural circuitry that vulnerability might lie. In her ongoing work, Riggs is zeroing in on a novel thalamocortical circuit between the anteromedial nucleus of the thalamus and the cingulate cortex, which she found drives anxiogenic states. Riggs is co-supervised by Professor Fan Wang.
After the wide-ranging talks, supplemented by further discussion at the panels, the last word came via video conference from Kelsey Martin, executive vice president of the Simons Foundation Autism Research Initiative. Martin emphasized that fundamental research, like that done at the Simons Center, is the key to developing future therapies and other means of supporting members of the autism community.
“We believe so strongly that understanding the basic mechanisms of autism is critical to being able to develop translational and clinical approaches that are going to impact the lives of autistic individuals and their families,” she said.
From studies of synapses to circuits to behavior, MIT researchers and their collaborators are striving for exactly that impact.
Physicists magnetize a material with lightThe technique provides researchers with a powerful tool for controlling magnetism, and could help in designing faster, smaller, more energy-efficient memory chips.MIT physicists have created a new and long-lasting magnetic state in a material, using only light.
In a study appearing today in Nature, the researchers report using a terahertz laser — a light source that oscillates more than a trillion times per second — to directly stimulate atoms in an antiferromagnetic material. The laser’s oscillations are tuned to the natural vibrations among the material’s atoms, in a way that shifts the balance of atomic spins toward a new magnetic state.
The results provide a new way to control and switch antiferromagnetic materials, which are of interest for their potential to advance information processing and memory chip technology.
In common magnets, known as ferromagnets, the spins of atoms point in the same direction, in a way that the whole can be easily influenced and pulled in the direction of any external magnetic field. In contrast, antiferromagnets are composed of atoms with alternating spins, each pointing in the opposite direction from its neighbor. This up, down, up, down order essentially cancels the spins out, giving antiferromagnets a net zero magnetization that is impervious to any magnetic pull.
If a memory chip could be made from antiferromagnetic material, data could be “written” into microscopic regions of the material, called domains. A certain configuration of spin orientations (for example, up-down) in a given domain would represent the classical bit “0,” and a different configuration (down-up) would mean “1.” Data written on such a chip would be robust against outside magnetic influence.
For this and other reasons, scientists believe antiferromagnetic materials could be a more robust alternative to existing magnetic-based storage technologies. A major hurdle, however, has been in how to control antiferromagnets in a way that reliably switches the material from one magnetic state to another.
“Antiferromagnetic materials are robust and not influenced by unwanted stray magnetic fields,” says Nuh Gedik, the Donner Professor of Physics at MIT. “However, this robustness is a double-edged sword; their insensitivity to weak magnetic fields makes these materials difficult to control.”
Using carefully tuned terahertz light, the MIT team was able to controllably switch an antiferromagnet to a new magnetic state. Antiferromagnets could be incorporated into future memory chips that store and process more data while using less energy and taking up a fraction of the space of existing devices, owing to the stability of magnetic domains.
“Generally, such antiferromagnetic materials are not easy to control,” Gedik says. “Now we have some knobs to be able to tune and tweak them.”
Gedik is the senior author of the new study, which also includes MIT co-authors Batyr Ilyas, Tianchuang Luo, Alexander von Hoegen, Zhuquan Zhang, and Keith Nelson, along with collaborators at the Max Planck Institute for the Structure and Dynamics of Matter in Germany, University of the Basque Country in Spain, Seoul National University, and the Flatiron Institute in New York.
Off balance
Gedik’s group at MIT develops techniques to manipulate quantum materials in which interactions among atoms can give rise to exotic phenomena.
“In general, we excite materials with light to learn more about what holds them together fundamentally,” Gedik says. “For instance, why is this material an antiferromagnet, and is there a way to perturb microscopic interactions such that it turns into a ferromagnet?”
In their new study, the team worked with FePS3 — a material that transitions to an antiferromagnetic phase at a critical temperature of around 118 kelvins (-247 degrees Fahrenheit).
The team suspected they might control the material’s transition by tuning into its atomic vibrations.
“In any solid, you can picture it as different atoms that are periodically arranged, and between atoms are tiny springs,” von Hoegen explains. “If you were to pull one atom, it would vibrate at a characteristic frequency which typically occurs in the terahertz range.”
The way in which atoms vibrate also relates to how their spins interact with each other. The team reasoned that if they could stimulate the atoms with a terahertz source that oscillates at the same frequency as the atoms’ collective vibrations, called phonons, the effect could also nudge the atoms’ spins out of their perfectly balanced, magnetically alternating alignment. Once knocked out of balance, atoms should have larger spins in one direction than the other, creating a preferred orientation that would shift the inherently nonmagnetized material into a new magnetic state with finite magnetization.
“The idea is that you can kill two birds with one stone: You excite the atoms’ terahertz vibrations, which also couples to the spins,” Gedik says.
Shake and write
To test this idea, the team worked with a sample of FePS3 that was synthesized by colleages at Seoul National University. They placed the sample in a vacuum chamber and cooled it down to temperatures at and below 118 K. They then generated a terahertz pulse by aiming a beam of near-infrared light through an organic crystal, which transformed the light into the terahertz frequencies. They then directed this terahertz light toward the sample.
“This terahertz pulse is what we use to create a change in the sample,” Luo says. “It’s like ‘writing’ a new state into the sample.”
To confirm that the pulse triggered a change in the material’s magnetism, the team also aimed two near-infrared lasers at the sample, each with an opposite circular polarization. If the terahertz pulse had no effect, the researchers should see no difference in the intensity of the transmitted infrared lasers.
“Just seeing a difference tells us the material is no longer the original antiferromagnet, and that we are inducing a new magnetic state, by essentially using terahertz light to shake the atoms,” Ilyas says.
Over repeated experiments, the team observed that a terahertz pulse successfully switched the previously antiferromagnetic material to a new magnetic state — a transition that persisted for a surprisingly long time, over several milliseconds, even after the laser was turned off.
“People have seen these light-induced phase transitions before in other systems, but typically they live for very short times on the order of a picosecond, which is a trillionth of a second,” Gedik says.
In just a few milliseconds, scientists now might have a decent window of time during which they could probe the properties of the temporary new state before it settles back into its inherent antiferromagnetism. Then, they might be able to identify new knobs to tweak antiferromagnets and optimize their use in next-generation memory storage technologies.
This research was supported, in part, by the U.S. Department of Energy, Materials Science and Engineering Division, Office of Basic Energy Sciences, and the Gordon and Betty Moore Foundation.
How humans continuously adapt while walking stablyResearch could help improve motor rehabilitation programs and assistive robot control.Researchers have developed a model that explains how humans adapt continuously during complex tasks, like walking, while remaining stable.
The findings were detailed in a recent paper published in the journal Nature Communications authored by Nidhi Seethapathi, an assistant professor in MIT’s Department of Brain and Cognitive Sciences; Barrett C. Clark, a robotics software engineer at Bright Minds Inc.; and Manoj Srinivasan, an associate professor in the Department of Mechanical and Aerospace Engineering at Ohio State University.
In episodic tasks, like reaching for an object, errors during one episode do not affect the next episode. In tasks like locomotion, errors can have a cascade of short-term and long-term consequences to stability unless they are controlled. This makes the challenge of adapting locomotion in a new environment more complex.
"Much of our prior theoretical understanding of adaptation has been limited to episodic tasks, such as reaching for an object in a novel environment," Seethapathi says. "This new theoretical model captures adaptation phenomena in continuous long-horizon tasks in multiple locomotor settings."
To build the model, the researchers identified general principles of locomotor adaptation across a variety of task settings, and developed a unified modular and hierarchical model of locomotor adaptation, with each component having its own unique mathematical structure.
The resulting model successfully encapsulates how humans adapt their walking in novel settings such as on a split-belt treadmill with each foot at a different speed, wearing asymmetric leg weights, and wearing an exoskeleton. The authors report that the model successfully reproduced human locomotor adaptation phenomena across novel settings in 10 prior studies and correctly predicted the adaptation behavior observed in two new experiments conducted as part of the study.
The model has potential applications in sensorimotor learning, rehabilitation, and wearable robotics.
"Having a model that can predict how a person will adapt to a new environment has immense utility for engineering better rehabilitation paradigms and wearable robot control," Seethapathi says. "You can think of a wearable robot itself as a new environment for the person to move in, and our model can be used to predict how a person will adapt for different robot settings. Understanding such human-robot adaptation is currently an experimentally intensive process, and our model could help speed up the process by narrowing the search space."
3 Questions: Tracking MIT graduates’ career trajectoriesDeborah Liverman, executive director of MIT Career Advising and Professional Development, offers a window into undergraduate and graduate students’ post-graduation paths.In a fall letter to MIT alumni, President Sally Kornbluth wrote: “[T]he world has never been more ready to reward our graduates for what they know — and know how to do.” During her tenure leading MIT Career Advising and Professional Development (CAPD), Deborah Liverman has seen firsthand how — and how well — MIT undergraduate and graduate students leverage their education to make an impact around the globe in academia, industry, entrepreneurship, medicine, government and nonprofits, and other professions. Here, Liverman shares her observations about trends in students’ career paths and the complexities of the job market they must navigate along the way.
Q: How do our students fare when they graduate from MIT?
A: We routinely survey our undergraduates and graduate students to track post-graduation outcomes, so fortunately we have a wealth of data. And ultimately, this enables us to stay on top of changes from year to year and to serve our students better.
The short answer is that our students fare exceptionally well when they leave the Institute! In our 2023 Graduating Student Survey, which is an exit survey for bachelor’s degree and master’s degree students, 49 percent of bachelor’s respondents and 79 percent of master’s respondents entered the workforce after graduating, and 43 percent and 14 percent started graduate school programs, respectively. Among those seeking immediate employment, 92 percent of bachelor’s and 87 percent of master’s degree students reported obtaining a job within three months of graduation.
What is notable, and frankly, wonderful, is that these two cohorts really took advantage of the rich ecosystem of experiential learning opportunities we have at MIT. The majority of Class of 2023 seniors participated in some form of experiential learning before graduation: 94 percent of them had a UROP [Undergraduate Research Opportunities Program], 75 percent interned, 66 percent taught or tutored, and 38 percent engaged with or mentored at campus makerspaces. Among master’s degree graduates in 2023, 56 percent interned, 45 percent taught or tutored, and 30 percent took part in entrepreneurial ventures or activities. About 47 percent of bachelor’s graduates said that a previous internship or externship led to the offer that they accepted, and 46 percent of master’s graduates are a founding member of a company.
We conduct a separate survey for doctoral students. I think there’s a common misperception that most of our PhD students go into academia. But a sizable portion choose not to stay in the academy. According to our 2024 Doctoral Exit Survey, 41 percent of graduates planned to go into industry. As of the survey date, of those who were going on to employment, 76 percent had signed a contract or made a definite commitment to a postdoc or other work, and only 9 percent were seeking a position but had no specific prospects.
A cohort of students, as well as some alumni, work with CAPD’s Prehealth Advising staff to apply for medical school. Last year we supported 73 students and alumni consisting of 25 undergrads, eight graduate students, and 40 alumni, with an acceptance rate of 79 percent — well above the national rate of 41 percent.
Q: How does CAPD work with students and postdocs to cultivate their professional development and help them evaluate their career options?
A: As you might expect, the career and graduate school landscape is constantly changing. In turn, CAPD strives to continuously evolve, so that we can best support and prepare our students. It certainly keeps us on our feet!
One of the things we have changed recently is our fundamental approach to working with students. We migrated our advising model from a major-specific focus to instead center on career interest areas. That allows us to prioritize skills and use a cross-disciplinary approach to advising students. So when an advisor sits down (or Zooms) with a student, that one-on-one session creates plenty of space to discuss a student’s individual values, goals, and other career-decision influencing factors.
I would say that another area we have been heavily focused on is providing new ways for students to explore careers. To that end, we developed two roles — an assistant director of career exploration and an assistant director of career prototype — to support new initiatives. And we provide career exploration fellowships and grants for undergraduate and graduate students so that they can explore fields that may be niche to MIT.
Career exploration is really important, but we want to meet students and postdocs where they are. We know they are incredibly busy at MIT, so our goal is to provide a variety of formats to make that possible, from a one-hour workshop or speaker, to a daylong shadowing experience, or a longer-term internship. For example, we partnered with departments to create the Career Exploration Series and the Infinite Careers speaker series, where we show students various avenues to get to a career. We have also created more opportunities to interact with alumni or other employers through one-day shadowing opportunities, micro-internships, internships, and employer coffee chats. The Prehealth Advising program I mentioned before offers many avenues to explore the field of medicine, so students can really make informed decisions about the path they want to pursue.
We are also looking at our existing programming to identify opportunities to build in career exploration, such as the Fall Career Fair. We have been working on identifying employers who are open to having career exploration conversations with — or hiring — first-year undergraduates, with access to these employers 30 minutes before the start of the fair. This year, the fair drew 4,400 candidates (students, postdocs, and alumni) and 180 employers, so it’s a great opportunity to leverage an event we already have in place and make it even more fruitful for both students and employers.
I do want to underscore that career exploration is just as important for graduate students as it is for undergraduates. In the doctoral exit survey I mentioned, 37 percent of 2024 graduates said they had changed their mind about the type of employer for whom they expected to work since entering their graduate program, and 38 percent had changed their mind about the type of position they expected to have. CAPD has developed exploration programming geared specifically for them, such as the CHAOS Process and our Graduate Student Professional Development offerings.
Q: What kinds of trends are you seeing in the current job market? And as students receive job offers, how do they weigh factors like the ethical considerations of working for a certain company or industry, the political landscape in the U.S. and abroad, the climate impact of a certain company or industry, or other issues?
A: Well, one notable trend is just the sheer volume of job applications. With platforms like LinkedIn’s Easy Apply, it’s easier for job seekers to apply to hundreds of jobs at once. Employers and organizations have more candidates, so applicants have to do more to stand out. Companies that, in the past, have had to seek out candidates are now deciding the best use of their recruiting efforts.
I would say the current job market is mixed. MIT students, graduates, and postdocs have experienced delayed job offers and starting dates pushed back in consulting and some tech firms. Companies are being intentional about recruiting and hiring college graduates. So students need to keep an open mind and not have their heart set on a particular employer. And if that employer isn’t hiring, then they may have to optimize their job search and consider other opportunities where they can gain experience.
On a more granular level, we do see trends in certain fields. Biotech has had a tough year, but there’s an uptick in opportunities in government, space, aerospace, and in the climate/sustainability and energy sectors. Companies are increasingly adopting AI in their business practices, so they’re hiring in that area. And financial services is a hot market for MIT candidates with strong technical skills.
As for how a student evaluates a job offer, according to the Graduating Student Survey, students look at many factors, including the job content, fit with the employer’s culture, opportunity for career advancement, and of course salary. However, students are also interested in exploring how an organization fits with their values.
CAPD provides various opportunities and resources to help them zero in on what matters most to them, from on-demand resources to one-on-one sessions with our advisors. As they research potential companies, we encourage them to make the most of career fairs and recruiting events. Throughout the academic year, MIT hosts and collaborates on over a dozen career fairs and large recruiting events. Companies are invited based on MIT candidates’ interests. The variety of opportunities means students can connect with different industries, explore careers, and apply to internships, jobs and research opportunities.
We also recommend that they take full advantage of MIT’s curated instance of Handshake, an online recruiting platform for higher education students and alumni. CAPD has collaborated with offices and groups to create filters and identifiers in Handshake to help candidates decide what is important to them, such as a company’s commitment to inclusive practices or their sustainability initiatives.
As advisors, we encourage each student to think about which factors are important for them when evaluating job offers and determine if an employer aligns with their values and goals. And we encourage and honor each student’s right to include those values and goals in their career decision-making process. Accepting a job is a very personal decision, and we are here to support each student every step of the way.
New climate chemistry model finds “non-negligible” impacts of potential hydrogen fuel leakageMIT study confirms the climate impacts of hydrogen, recommends leak prevention be a priority as infrastructure for handling this clean-burning fuel is built.As the world looks for ways to stop climate change, much discussion focuses on using hydrogen instead of fossil fuels, which emit climate-warming greenhouse gases (GHGs) when they’re burned. The idea is appealing. Burning hydrogen doesn’t emit GHGs to the atmosphere, and hydrogen is well-suited for a variety of uses, notably as a replacement for natural gas in industrial processes, power generation, and home heating.
But while burning hydrogen won’t emit GHGs, any hydrogen that’s leaked from pipelines or storage or fueling facilities can indirectly cause climate change by affecting other compounds that are GHGs, including tropospheric ozone and methane, with methane impacts being the dominant effect. A much-cited 2022 modeling study analyzing hydrogen’s effects on chemical compounds in the atmosphere concluded that these climate impacts could be considerable. With funding from the MIT Energy Initiative’s Future Energy Systems Center, a team of MIT researchers took a more detailed look at the specific chemistry that poses the risks of using hydrogen as a fuel if it leaks.
The researchers developed a model that tracks many more chemical reactions that may be affected by hydrogen and includes interactions among chemicals. Their open-access results, published Oct. 28 in Frontiers in Energy Research, showed that while the impact of leaked hydrogen on the climate wouldn’t be as large as the 2022 study predicted — and that it would be about a third of the impact of any natural gas that escapes today — leaked hydrogen will impact the climate. Leak prevention should therefore be a top priority as the hydrogen infrastructure is built, state the researchers.
Hydrogen’s impact on the “detergent” that cleans our atmosphere
Global three-dimensional climate-chemistry models using a large number of chemical reactions have also been used to evaluate hydrogen’s potential climate impacts, but results vary from one model to another, motivating the MIT study to analyze the chemistry. Most studies of the climate effects of using hydrogen consider only the GHGs that are emitted during the production of the hydrogen fuel. Different approaches may make “blue hydrogen” or “green hydrogen,” a label that relates to the GHGs emitted. Regardless of the process used to make the hydrogen, the fuel itself can threaten the climate. For widespread use, hydrogen will need to be transported, distributed, and stored — in short, there will be many opportunities for leakage.
The question is, What happens to that leaked hydrogen when it reaches the atmosphere? The 2022 study predicting large climate impacts from leaked hydrogen was based on reactions between pairs of just four chemical compounds in the atmosphere. The results showed that the hydrogen would deplete a chemical species that atmospheric chemists call the “detergent of the atmosphere,” explains Candice Chen, a PhD candidate in MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS). “It goes around zapping greenhouse gases, pollutants, all sorts of bad things in the atmosphere. So it’s cleaning our air.” Best of all, that detergent — the hydroxyl radical, abbreviated as OH — removes methane, which is an extremely potent GHG in the atmosphere. OH thus plays an important role in slowing the rate at which global temperatures rise. But any hydrogen leaked to the atmosphere would reduce the amount of OH available to clean up methane, so the concentration of methane would increase.
However, chemical reactions among compounds in the atmosphere are notoriously complicated. While the 2022 study used a “four-equation model,” Chen and her colleagues — Susan Solomon, the Lee and Geraldine Martin Professor of Environmental Studies and Chemistry; and Kane Stone, a research scientist in EAPS — developed a model that includes 66 chemical reactions. Analyses using their 66-equation model showed that the four-equation system didn’t capture a critical feedback involving OH — a feedback that acts to protect the methane-removal process.
Here’s how that feedback works: As the hydrogen decreases the concentration of OH, the cleanup of methane slows down, so the methane concentration increases. However, that methane undergoes chemical reactions that can produce new OH radicals. “So the methane that’s being produced can make more of the OH detergent,” says Chen. “There’s a small countering effect. Indirectly, the methane helps produce the thing that’s getting rid of it.” And, says Chen, that’s a key difference between their 66-equation model and the four-equation one. “The simple model uses a constant value for the production of OH, so it misses that key OH-production feedback,” she says.
To explore the importance of including that feedback effect, the MIT researchers performed the following analysis: They assumed that a single pulse of hydrogen was injected into the atmosphere and predicted the change in methane concentration over the next 100 years, first using four-equation model and then using the 66-equation model. With the four-equation system, the additional methane concentration peaked at nearly 2 parts per billion (ppb); with the 66-equation system, it peaked at just over 1 ppb.
Because the four-equation analysis assumes only that the injected hydrogen destroys the OH, the methane concentration increases unchecked for the first 10 years or so. In contrast, the 66-equation analysis goes one step further: the methane concentration does increase, but as the system re-equilibrates, more OH forms and removes methane. By not accounting for that feedback, the four-equation analysis overestimates the peak increase in methane due to the hydrogen pulse by about 85 percent. Spread over time, the simple model doubles the amount of methane that forms in response to the hydrogen pulse.
Chen cautions that the point of their work is not to present their result as “a solid estimate” of the impact of hydrogen. Their analysis is based on a simple “box” model that represents global average conditions and assumes that all the chemical species present are well mixed. Thus, the species can vary over time — that is, they can be formed and destroyed — but any species that are present are always perfectly mixed. As a result, a box model does not account for the impact of, say, wind on the distribution of species. “The point we're trying to make is that you can go too simple,” says Chen. “If you’re going simpler than what we're representing, you will get further from the right answer.” She goes on to note, “The utility of a relatively simple model like ours is that all of the knobs and levers are very clear. That means you can explore the system and see what affects a value of interest.”
Leaked hydrogen versus leaked natural gas: A climate comparison
Burning natural gas produces fewer GHG emissions than does burning coal or oil; but as with hydrogen, any natural gas that’s leaked from wells, pipelines, and processing facilities can have climate impacts, negating some of the perceived benefits of using natural gas in place of other fossil fuels. After all, natural gas consists largely of methane, the highly potent GHG in the atmosphere that’s cleaned up by the OH detergent. Given its potency, even small leaks of methane can have a large climate impact.
So when thinking about replacing natural gas fuel — essentially methane — with hydrogen fuel, it’s important to consider how the climate impacts of the two fuels compare if and when they’re leaked. The usual way to compare the climate impacts of two chemicals is using a measure called the global warming potential, or GWP. The GWP combines two measures: the radiative forcing of a gas — that is, its heat-trapping ability — with its lifetime in the atmosphere. Since the lifetimes of gases differ widely, to compare the climate impacts of two gases, the convention is to relate the GWP of each one to the GWP of carbon dioxide.
But hydrogen and methane leakage cause increases in methane, and that methane decays according to its lifetime. Chen and her colleagues therefore realized that an unconventional procedure would work: they could compare the impacts of the two leaked gases directly. What they found was that the climate impact of hydrogen is about three times less than that of methane (on a per mass basis). So switching from natural gas to hydrogen would not only eliminate combustion emissions, but also potentially reduce the climate effects, depending on how much leaks.
Key takeaways
In summary, Chen highlights some of what she views as the key findings of the study. First on her list is the following: “We show that a really simple four-equation system is not what should be used to project out the atmospheric response to more hydrogen leakages in the future.” The researchers believe that their 66-equation model is a good compromise for the number of chemical reactions to include. It generates estimates for the GWP of methane “pretty much in line with the lower end of the numbers that most other groups are getting using much more sophisticated climate chemistry models,” says Chen. And it’s sufficiently transparent to use in exploring various options for protecting the climate. Indeed, the MIT researchers plan to use their model to examine scenarios that involve replacing other fossil fuels with hydrogen to estimate the climate benefits of making the switch in coming decades.
The study also demonstrates a valuable new way to compare the greenhouse effects of two gases. As long as their effects exist on similar time scales, a direct comparison is possible — and preferable to comparing each with carbon dioxide, which is extremely long-lived in the atmosphere. In this work, the direct comparison generates a simple look at the relative climate impacts of leaked hydrogen and leaked methane — valuable information to take into account when considering switching from natural gas to hydrogen.
Finally, the researchers offer practical guidance for infrastructure development and use for both hydrogen and natural gas. Their analyses determine that hydrogen fuel itself has a “non-negligible” GWP, as does natural gas, which is mostly methane. Therefore, minimizing leakage of both fuels will be necessary to achieve net-zero carbon emissions by 2050, the goal set by both the European Commission and the U.S. Department of State. Their paper concludes, “If used nearly leak-free, hydrogen is an excellent option. Otherwise, hydrogen should only be a temporary step in the energy transition, or it must be used in tandem with carbon-removal steps [elsewhere] to counter its warming effects.”
Artifacts from a half-century of cancer researchTen objects on display in the Koch Institute Public Galleries offer uncommon insights into the people and progress of MIT's cancer research community.Throughout 2024, MIT’s Koch Institute for Integrative Cancer Research has celebrated 50 years of MIT’s cancer research program and the individuals who have shaped its journey. In honor of this milestone anniversary year, on Nov. 19 the Koch Institute celebrated the opening of a new exhibition: Object Lessons: Celebrating 50 Years of Cancer Research at MIT in 10 Items.
Object Lessons invites the public to explore significant artifacts — from one of the earliest PCR machines, developed in the lab of Nobel laureate H. Robert Horvitz, to Greta, a groundbreaking zebra fish from the lab of Professor Nancy Hopkins — in the half-century of discoveries and advancements that have positioned MIT at the forefront of the fight against cancer.
50 years of innovation
The exhibition provides a glimpse into the many contributors and advancements that have defined MIT’s cancer research history since the founding of the Center for Cancer Research in 1974. When the National Cancer Act was passed in 1971, very little was understood about the biology of cancer, and it aimed to deepen our understanding of cancer and develop better strategies for the prevention, detection, and treatment of the disease. MIT embraced this call to action, establishing a center where many leading biologists tackled cancer’s fundamental questions. Building on this foundation, the Koch Institute opened its doors in 2011, housing engineers and life scientists from many fields under one roof to accelerate progress against cancer in novel and transformative ways.
In the 13 years since, the Koch Institute’s collaborative and interdisciplinary approach to cancer research has yielded significant advances in our understanding of the underlying biology of cancer and allowed for the translation of these discoveries into meaningful patient impacts. Over 120 spin-out companies — many headquartered nearby in the Kendall Square area — have their roots in Koch Institute research, with nearly half having advanced their technologies to clinical trials or commercial applications. The Koch Institute’s collaborative approach extends beyond its labs: principal investigators often form partnerships with colleagues at world-renowned medical centers, bridging the gap between discovery and clinical impact.
Current Koch Institute Director Matthew Vander Heiden, also a practicing oncologist at the Dana-Farber Cancer Institute, is driven by patient stories.
“It is never lost on us that the work we do in the lab is important to change the reality of cancer for patients,” he says. “We are constantly motivated by the urgent need to translate our research and improve outcomes for those impacted by cancer.”
Symbols of progress
The items on display as part of Object Lessons take viewers on a journey through five decades of MIT cancer research, from the pioneering days of Salvador Luria, founding director of the Center for Cancer Research, to some of the Koch Institute’s newest investigators, including Francisco Sánchez-Rivera, the Eisen and Chang Career Development Professor and an assistant professor of biology, and Jessica Stark, the Underwood-Prescott Career Development Professor and an assistant professor of biological engineering and chemical engineering.
Among the standout pieces is a humble yet iconic object: Salvador Luria’s ceramic mug, emblazoned with “Luria’s broth.” Lysogeny broth, often called — apocryphally — Luria Broth, is a medium for growing bacteria. Still in use today, the recipe was first published in 1951 by a research associate in Luria’s lab. The artifact, on loan from the MIT Museum, symbolizes the foundational years of the Center for Cancer Research and serves as a reminder of Luria’s influence as an early visionary. His work set the stage for a new era of biological inquiry that would shape cancer research at MIT for generations.
Visitors can explore firsthand how the Koch Institute continues to build on the legacy of its predecessors, translating decades of knowledge into new tools and therapies that have the potential to transform patient care and cancer research.
For instance, the PCR machine designed in the Horvitz Lab in the 1980s made genetic manipulation of cells easier, and gene sequencing faster and more cost-effective. At the time of its commercialization, this groundbreaking benchtop unit marked a major leap forward. In the decades since, technological advances have allowed for the visualization of DNA and biological processes at a much smaller scale, as demonstrated by the handheld BioBits imaging device developed by Stark and on display next door to the Horvitz panel.
“We created BioBits kits to address a need for increased equity in STEM education,” Stark says. “By making hands-on biology education approachable and affordable, BioBits kits are helping inspire and empower the next generation of scientists."
While the exhibition showcases scientific discoveries and marvels of engineering, it also aims to underscore the human element of cancer research through personally significant items, such as a messenger bag and Seq-Well device belonging to Alex Shalek, J. W. Kieckhefer Professor in the Institute for Medical Engineering and Science and the Department of Chemistry.
Shalek investigates the molecular differences between individual cells, developing mobile RNA-sequencing devices. He could often be seen toting the bag around the Boston area and worldwide as he perfected and shared his technology with collaborators near and far. Through his work, Shalek has helped to make single-cell sequencing accessible for labs in more than 30 countries across six continents.
“The KI seamlessly brings together students, staff, clinicians, and faculty across multiple different disciplines to collaboratively derive transformative insights into cancer,” Shalek says. “To me, these sorts of partnerships are the best part about being at MIT.”
Around the corner from Shalek’s display, visitors will find an object that serves as a stark reminder of the real people impacted by Koch Institute research: Steven Keating’s SM ’12, PhD ’16 3D-printed model of his own brain tumor. Keating, who passed away in 2019, became a fierce advocate for the rights of patients to their medical data, and came to know Vander Heiden through his pursuit to become an expert on his tumor type, IDH-mutant glioma. In the years since, Vander Heiden’s work has contributed to a new therapy to treat Keating’s tumor type. In 2024, the drug, called vorasidenib, gained FDA approval, providing the first therapeutic breakthrough for Keating’s cancer in more than 20 years.
As the Koch Institute looks to the future, Object Lessons stands as a celebration of the people, the science, and the culture that have defined MIT’s first half-century of breakthroughs and contributions to the field of cancer research.
“Working in the uniquely collaborative environment of the Koch Institute and MIT, I am confident that we will continue to unlock key insights in the fight against cancer,” says Vander Heiden. “Our community is poised to embark on our next 50 years with the same passion and innovation that has carried us this far.”
Object Lessons is on view in the Koch Institute Public Galleries Monday through Friday, 9 a.m. to 5 p.m., through spring semester 2025.
Brought together as part of the Social and Ethical Responsibilities of Computing (SERC) initiative within the MIT Schwarzman College of Computing, a community of students known as SERC Scholars is collaborating to examine the most urgent problems humans face in the digital landscape.
Each semester, students from all levels from across MIT are invited to join a different topical working group led by a SERC postdoctoral associate. Each group delves into a specific issue — such as surveillance or data ownership — culminating in a final project presented at the end of the term.
Typically, students complete the program with hands-on experience conducting research in a new cross-disciplinary field. However, one group of undergraduate and graduate students recently had the unique opportunity to enhance their resume by becoming published authors of a case study about the environmental and climate justice implications of the electronics hardware life cycle.
Although it’s not uncommon for graduate students to co-author case studies, it’s unusual for undergraduates to earn this opportunity — and for their audience to be other undergraduates around the world.
“Our team was insanely interdisciplinary,” says Anastasia Dunca, a junior studying computer science and one of the co-authors. “I joined the SERC Scholars Program because I liked the idea of being part of a cohort from across MIT working on a project that utilized all of our skillsets. It also helps [undergraduates] learn the ins and outs of computing ethics research.”
Case study co-author Jasmin Liu, an MBA student in the MIT Sloan School of Management, sees the program as a platform to learn about the intersection of technology, society, and ethics: “I met team members spanning computer science, urban planning, to art/culture/technology. I was excited to work with a diverse team because I know complex problems must be approached with many different perspectives. Combining my background in humanities and business with the expertise of others allowed us to be more innovative and comprehensive.”
Christopher Rabe, a former SERC postdoc who facilitated the group, says, “I let the students take the lead on identifying the topic and conducting the research.” His goal for the group was to challenge students across disciplines to develop a working definition of climate justice.
From mining to e-waste
The SERC Scholars’ case study, “From Mining to E-waste: The Environmental and Climate Justice Implications of the Electronics Hardware Life Cycle,” was published by the MIT Case Studies in Social and Ethical Responsibilities of Computing.
The ongoing case studies series, which releases new issues twice a year on an open-source platform, is enabling undergraduate instructors worldwide to incorporate research-based education materials on computing ethics into their existing class syllabi.
This particular case study broke down the electronics life cycle from mining to manufacturing, usage, and disposal. It offered an in-depth look at how this cycle promotes inequity in the Global South. Mining for the average of 60 minerals that power everyday devices lead to illegal deforestation, compromising air quality in the Amazon, and triggering armed conflict in Congo. Manufacturing leads to proven health risks for both formal and informal workers, some of whom are child laborers.
Life cycle assessment and circular economy are proposed as mechanisms for analyzing environmental and climate justice issues in the electronics life cycle. Rather than posing solutions, the case study offers readers entry points for further discussion and for assessing their own individual responsibility as producers of e-waste.
Crufting and crafting a case study
Dunca joined Rabe's working group, intrigued by the invitation to conduct a rigorous literature review examining issues like data center resource and energy use, manufacturing waste, ethical issues with AI, and climate change. Rabe quickly realized that a common thread among all participants was an interest in understanding and reducing e-waste and its impact on the environment.
“I came in with the idea of us co-authoring a case study,” Rabe said. However, the writing-intensive process was initially daunting to those students who were used to conducting applied research. Once Rabe created sub-groups with discrete tasks, the steps for researching, writing, and iterating a case study became more approachable.
For Ellie Bultena, an undergraduate student studying linguistics and philosophy and a contributor to the study, that meant conducting field research on the loading dock of MIT’s Stata Center, where students and faculty go “crufting” through piles of clunky printers, broken computers, and used lab equipment discarded by the Institute's labs, departments, and individual users.
Although not a formally sanctioned activity on-campus, “crufting” is the act of gleaning usable parts from these junk piles to be repurposed into new equipment or art. Bultena’s respondents, who opted to be anonymous, said that MIT could do better when it comes to the amount of e-waste generated and suggested that formal strategies could be implemented to encourage community members to repair equipment more easily or recycle more formally.
Rabe, now an education program director at the MIT Environmental Solutions Initiative, is hopeful that through the Zero-Carbon Campus Initiative, which commits MIT to eliminating all direct emissions by 2050, MIT will ultimately become a model for other higher education institutions.
Although the group lacked the time and resources to travel to communities in the Global South that they profiled in their case study, members leaned into exhaustive secondary research, collecting data on how some countries are irresponsibly dumping e-waste. In contrast, others have developed alternative solutions that can be duplicated elsewhere and scaled.
“We source materials, manufacture them, and then throw them away,” Lelia Hampton says. A PhD candidate in electrical engineering and computer science and another co-author, Hampton jumped at the opportunity to serve in a writing role, bringing together the sub-groups research findings. “I’d never written a case study, and it was exciting. Now I want to write 10 more.”
The content directly informed Hampton’s dissertation research, which “looks at applying machine learning to climate justice issues such as urban heat islands.” She said that writing a case study that is accessible to general audiences upskilled her for the non-profit organization she’s determined to start. “It’s going to provide communities with free resources and data needed to understand how they are impacted by climate change and begin to advocate against injustice,” Hampton explains.
Dunca, Liu, Rabe, Bultena, and Hampton are joined on the case study by fellow authors Mrinalini Singha, a graduate student in the Art, Culture, and Technology program; Sungmoon Lim, a graduate student in urban studies and planning and EECS; Lauren Higgins, an undergraduate majoring in political science; and Madeline Schlegel, a Northeastern University co-op student.
Taking the case study to classrooms around the world
Although PhD candidates have contributed to previous case studies in the series, this publication is the first to be co-authored with MIT undergraduates. Like any other peer-reviewed journal, before publication, the SERC Scholars’ case study was anonymously reviewed by senior scholars drawn from various fields.
The series editor, David Kaiser, also served as one of SERC’s inaugural associate deans and helped shape the program. “The case studies, by design, are short, easy to read, and don't take up lots of time,” Kaiser explained. “They are gateways for students to explore, and instructors can cover a topic that has likely already been on their mind.” This semester, Kaiser, the Germeshausen Professor of the History of Science and a professor of physics, is teaching STS.004 (Intersections: Science, Technology, and the World), an undergraduate introduction to the field of science, technology, and society. The last month of the semester has been dedicated wholly to SERC case studies, one of which is: “From Mining to E-Waste.”
Hampton was visibly moved to hear that the case study is being used at MIT but also by some of the 250,000 visitors to the SERC platform, many of whom are based in the Global South and directly impacted by the issues she and her cohort researched. “Many students are focused on climate, whether through computer science, data science, or mechanical engineering. I hope that this case study educates them on environmental and climate aspects of e-waste and computing.”
Photos: 2024 Nobel winners with MIT ties honored in StockholmLaureates participated in various Nobel Week events, including lectures, a concert, a banquet, and the Nobel ceremony on Dec. 10.MIT-affiliated winners of the 2024 Nobel Prizes were celebrated in Stockholm, Sweden, as part of Nobel Week, which culminated with a grand Nobel ceremony on Dec. 10.
This year’s laureates with MIT ties include Daron Acemoglu, an Institute Professor, and Simon Johnson, the Ronald A. Kurtz Professor of Entrepreneurship, who together shared the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel, along with James Robinson of the University of Chicago, for their work on the relationship between economic growth and political institutions. MIT Department of Biology alumnus Victor Ambros ’75, PhD ’79 also shared the Nobel Prize in Physiology or Medicine with Gary Ruvkun, who completed his postdoctoral research at the Institute alongside Ambros in the 1980s. The two were honored for their discovery of MicroRNA.
The honorees and their invited guests took part in a number of activities in Stockholm during this year’s Nobel Week, which began Dec. 5 with press conferences and a tour of special Nobel Week Lights around the city. Lectures, a visit to the Nobel Prize Museum, and a concert followed.
Per tradition, the winners received their medals from King Carl XVI Gustaf of Sweden on Dec. 10, the anniversary of the death of Alfred Nobel. (Winners of the Nobel Peace Prize were honored on the same day in Oslo, Norway.)
At least 105 MIT affiliates — including faculty, staff, alumni, and others — have won Nobel Prizes, according to MIT Institutional Research. Photos from the festivities appear below.
Cellular traffic congestion in chronic diseases suggests new therapeutic targetsChronic diseases like diabetes are prevalent, costly, and challenging to treat. A common denominator driving them may be a promising new therapeutic target.Chronic diseases like Type 2 diabetes and inflammatory disorders have a huge impact on humanity. They are a leading cause of disease burden and deaths around the globe, are physically and economically taxing, and the number of people with such diseases is growing.
Treating chronic disease has proven difficult because there is not one simple cause, like a single gene mutation, that a treatment could target. At least, that’s how it has appeared to scientists. However, new research from MIT professor of biology and Whitehead Institute for Biomedical Research member Richard Young and colleagues, published in the journal Cell on Nov. 27, reveals that many chronic diseases have a common denominator that could be driving their dysfunction: reduced protein mobility.
What this means is that around half of all proteins active in cells slow their movement when cells are in a chronic disease state, reducing the proteins’ functions. The researchers’ findings suggest that protein mobility may be a linchpin for decreased cellular function in chronic disease, making it a promising therapeutic target.
In their paper, Young and colleagues in his lab, including MIT postdoc Alessandra Dall’Agnese, graduate students Shannon Moreno and Ming Zheng, and Research Scientist Tong Ihn Lee, describe their discovery of this common mobility defect, which they call proteolethargy; explain what causes the defect and how it leads to dysfunction in cells; and propose a new therapeutic hypothesis for treating chronic diseases.
“I’m excited about what this work could mean for patients,” says Dall’Agnese. “My hope is that this will lead to a new class of drugs that restore protein mobility, which could help people with many different diseases that all have this mechanism as a common denominator.”
“This work was a collaborative, interdisciplinary effort that brought together biologists, physicists, chemists, computer scientists and physician-scientists,” Lee says. “Combining that expertise is a strength of the Young lab. Studying the problem from different viewpoints really helped us think about how this mechanism might work and how it could change our understanding of the pathology of chronic disease.”
Commuter delays cause work stoppages in the cell
How do proteins moving more slowly through a cell lead to widespread and significant cellular dysfunction? Dall’Agnese explains that every cell is like a tiny city, with proteins as the workers who keep everything running. Proteins have to commute in dense traffic in the cell, traveling from where they are created to where they work. The faster their commute, the more work they get done. Now, imagine a city that starts experiencing traffic jams along all the roads. Stores don’t open on time, groceries are stuck in transit, meetings are postponed. Essentially all operations in the city are slowed.
The slowdown of operations in cells experiencing reduced protein mobility follows a similar progression. Normally, most proteins zip around the cell bumping into other molecules until they locate the molecule they work with or act on. The slower a protein moves, the fewer other molecules it will reach, and so the less likely it will be able to do its job. Young and colleagues found that such protein slowdowns lead to measurable reductions in the functional output of the proteins. When many proteins fail to get their jobs done in time, cells begin to experience a variety of problems — as they are known to do in chronic diseases.
Discovering the protein mobility problem
Young and colleagues first suspected that cells affected in chronic disease might have a protein mobility problem after observing changes in the behavior of the insulin receptor, a signaling protein that reacts to the presence of insulin and causes cells to take in sugar from blood. In people with diabetes, cells become less responsive to insulin — a state called insulin resistance — causing too much sugar to remain in the blood. In research published on insulin receptors in Nature Communications in 2022, Young and colleagues reported that insulin receptor mobility might be relevant to diabetes.
Knowing that many cellular functions are altered in diabetes, the researchers considered the possibility that altered protein mobility might somehow affect many proteins in cells. To test this hypothesis, they studied proteins involved in a broad range of cellular functions, including MED1, a protein involved in gene expression; HP1α, a protein involved in gene silencing; FIB1, a protein involved in production of ribosomes; and SRSF2, a protein involved in splicing of messenger RNA. They used single-molecule tracking and other methods to measure how each of those proteins moves in healthy cells and in cells in disease states. All but one of the proteins showed reduced mobility (about 20-35 percent) in the disease cells.
“I’m excited that we were able to transfer physics-based insight and methodology, which are commonly used to understand the single-molecule processes like gene transcription in normal cells, to a disease context and show that they can be used to uncover unexpected mechanisms of disease,” Zheng says. “This work shows how the random walk of proteins in cells is linked to disease pathology.”
Moreno concurs: “In school, we’re taught to consider changes in protein structure or DNA sequences when looking for causes of disease, but we’ve demonstrated that those are not the only contributing factors. If you only consider a static picture of a protein or a cell, you miss out on discovering these changes that only appear when molecules are in motion.”
Can’t commute across the cell, I’m all tied up right now
Next, the researchers needed to determine what was causing the proteins to slow down. They suspected that the defect had to do with an increase in cells of the level of reactive oxygen species (ROS), molecules that are highly prone to interfering with other molecules and their chemical reactions. Many types of chronic-disease-associated triggers, such as higher sugar or fat levels, certain toxins, and inflammatory signals, lead to an increase in ROS, also known as an increase in oxidative stress. The researchers measured the mobility of the proteins again, in cells that had high levels of ROS and were not otherwise in a disease state, and saw comparable mobility defects, suggesting that oxidative stress was to blame for the protein mobility defect.
The final part of the puzzle was why some, but not all, proteins slow down in the presence of ROS. SRSF2 was the only one of the proteins that was unaffected in the experiments, and it had one clear difference from the others: its surface did not contain any cysteines, an amino acid building block of many proteins. Cysteines are especially susceptible to interference from ROS because it will cause them to bond to other cysteines. When this bonding occurs between two protein molecules, it slows them down because the two proteins cannot move through the cell as quickly as either protein alone.
About half of the proteins in our cells contain surface cysteines, so this single protein mobility defect can impact many different cellular pathways. This makes sense when one considers the diversity of dysfunctions that appear in cells of people with chronic diseases: dysfunctions in cell signaling, metabolic processes, gene expression and gene silencing, and more. All of these processes rely on the efficient functioning of proteins — including the diverse proteins studied by the researchers. Young and colleagues performed several experiments to confirm that decreased protein mobility does in fact decrease a protein’s function. For example, they found that when an insulin receptor experiences decreased mobility, it acts less efficiently on IRS1, a molecule to which it usually adds a phosphate group.
From understanding a mechanism to treating a disease
Discovering that decreased protein mobility in the presence of oxidative stress could be driving many of the symptoms of chronic disease provides opportunities to develop therapies to rescue protein mobility. In the course of their experiments, the researchers treated cells with an antioxidant drug — something that reduces ROS — called N-acetyl cysteine and saw that this partially restored protein mobility.
The researchers are pursuing a variety of follow-ups to this work, including the search for drugs that safely and efficiently reduce ROS and restore protein mobility. They developed an assay that can be used to screen drugs to see if they restore protein mobility by comparing each drug’s effect on a simple biomarker with surface cysteines to one without. They are also looking into other diseases that may involve protein mobility, and are exploring the role of reduced protein mobility in aging.
“The complex biology of chronic diseases has made it challenging to come up with effective therapeutic hypotheses,” says Young. “The discovery that diverse disease-associated stimuli all induce a common feature, proteolethargy, and that this feature could contribute to much of the dysregulation that we see in chronic disease, is something that I hope will be a real game-changer for developing drugs that work across the spectrum of chronic diseases.”
Revisiting reinforcement learningA detailed new look at dopamine signaling suggests neuroscientists’ model of reinforcement learning may need to be revised.Dopamine is a powerful signal in the brain, influencing our moods, motivations, movements, and more. The neurotransmitter is crucial for reward-based learning, a function that may be disrupted in a number of psychiatric conditions, from mood disorders to addiction.
Now, researchers led by MIT Institute Professor Ann Graybiel have found surprising patterns of dopamine signaling that suggest neuroscientists may need to refine their model of how reinforcement learning occurs in the brain. The team’s findings were published recently in the journal Nature Communications.
Dopamine plays a critical role in teaching people and other animals about the cues and behaviors that portend both positive and negative outcomes; the classic example of this type of learning is the dog that Ivan Pavlov trained to anticipate food at the sound of bell. Graybiel, who is also an investigator at MIT's McGovern Institute, explains that according to the standard model of reinforcement learning, when an animal is exposed to a cue paired with a reward, dopamine-producing cells initially fire in response to the reward. As animals learn the association between the cue and the reward, the timing of dopamine release shifts, so it becomes associated with the cue instead of the reward itself.
But with new tools enabling more detailed analyses of when and where dopamine is released in the brain, Graybiel’s team is finding that this model doesn’t completely hold up. The group started picking up clues that the field’s model of reinforcement learning was incomplete more than 10 years ago, when Mark Howe, a graduate student in the lab, noticed that the dopamine signals associated with reward were released not in a sudden burst the moment a reward was obtained, but instead before that, building gradually as a rat got closer to its treat. Dopamine might actually be communicating to the rest of the brain the proximity of the reward, they reasoned. “That didn't fit at all with the standard, canonical model,” Graybiel says.
Dopamine dynamics
As other neuroscientists considered how a model of reinforcement learning could take those findings into account, Graybiel and postdoc Min Jung Kim decided it was time to take a closer look at dopamine dynamics. “We thought: Let's go back to the most basic kind of experiment and start all over again,” she says.
That meant using sensitive new dopamine sensors to track the neurotransmitter’s release in the brains of mice as they learned to associated a blue light with a satisfying sip of water. The team focused its attention on the striatum, a region within the brain’s basal ganglia, where neurons use dopamine to influence neural circuits involved in a variety of processes, including reward-based learning.
The researchers found that the timing of dopamine release varied in different parts of the striatum. But nowhere did Graybiel’s team find a transition in dopamine release timing from the time of the reward to the time to the cue — the key transition predicted by the standard model of reinforcement learning model.
In the team’s simplest experiments, where every time a mouse saw a light it was paired with a reward, the lateral part of the striatum reliably released dopamine when animals were given their water. This strong response to the reward never diminished, even as the mice learned to expect the reward when they saw a light. In the medial part of the striatum, in contrast, dopamine was never released at the time of the reward. Cells there always fired when a mouse saw the light, even early in the learning process. This was puzzling, Graybiel says, because at the beginning of learning, dopamine would have been predicted to respond to the reward itself.
The patterns of dopamine release became even more unexpected when Graybiel’s team introduced a second light into its experimental setup. The new light, in a different position than the first, did not signal a reward. Mice watched as either light was given as the cue, one at a time, with water accompanying only the original cue.
In these experiments, when the mice saw the reward-associated light, dopamine release went up in the centromedial striatum and surprisingly, stayed up until the reward was delivered. In the lateral part of the region, dopamine also involved a sustained period where signaling plateaued.
Graybiel says she was surprised to see how much dopamine responses changed when the experimenters introduce the second light. The responses to the rewarded light were different when the other light could be shown in other trials, even though the mice saw only one light at a time. “There must be a cognitive aspect to this that comes into play,” she says. “The brain wants to hold onto the information that the cue has come on for a while.” Cells in the striatum seem to achieve this through the sustained dopamine release that continued during the brief delay between the light and the reward in the team’s experiments. Indeed, Graybiel says, while this kind of sustained dopamine release has not previously been linked to reinforcement learning, it is reminiscent of sustained signaling that has been tied to working memory in other parts of the brain.
Reinforcement learning, reconsidered
Ultimately, Graybiel says, “many of our results didn't fit reinforcement learning models as traditionally — and by now canonically — considered.” That suggests neuroscientists’ understanding of this process will need to evolve as part of the field’s deepening understanding of the brain. “But this is just one step to help us all refine our understanding and to have reformulations of the models of how basal ganglia influence movement and thought and emotion. These reformulations will have to include surprises about the reinforcement learning system vis-á-vis these plateaus, but they could possibly give us insight into how a single experience can linger in this reinforcement-related part of our brains,” she says.
This study was funded by the National Institutes of Health, the William N. and Bernice E. Bumpus Foundation, the Saks Kavanaugh Foundation, the CHDI Foundation, Joan and Jim Schattinger, and Lisa Yang.
Professor Emeritus Hale Van Dorn Bradt, an X-ray astronomy pioneer, dies at 93Longtime MIT faculty member used X-ray astronomy to study neutron stars and black holes and led the All-Sky Monitor instrument on NASA's Rossi X-ray Timing Explorer.MIT Professor Emeritus Hale Van Dorn Bradt PhD ’61 of Peabody, Massachusetts, formerly of Salem and Belmont, beloved husband of Dorothy A. (Haughey) Bradt, passed away on Thursday, Nov. 14 at Salem Hospital, surrounded by his loving family. He was 93.
Bradt, a longtime member of the Department of Physics, worked primarily in X-ray astronomy with NASA rockets and satellites, studying neutron stars and black holes in X-ray binary systems using rocket-based and satellite-based instrumentation. He was the original principal investigator for the All-Sky Monitor instrument on NASA's Rossi X-ray Timing Explorer (RXTE), which operated from 1996 to 2012.
Much of his research was directed toward determining the precise locations of celestial X-ray sources, most of which were neutron stars or black holes. This made possible investigations of their intrinsic natures at optical, radio, and X-ray wavelengths.
“Hale was the last of the cosmic ray group that converted to X-ray astronomy,” says Bruno Rossi Professor of Physics Claude Canizares. “He was devoted to undergraduate teaching and, as a postdoc, I benefited personally from his mentoring and guidance.”
He shared the Bruno Rossi Prize in High-Energy Astrophysics from the American Astronomical Society in 1999.
Bradt earned his PhD at MIT in 1961, working with advisor George Clark in cosmic ray physics, and taught undergraduate courses in physics from 1963 to 2001.
In the 1970s, he created the department's undergraduate astrophysics electives 8.282 and 8.284, which are still offered today. He wrote two textbooks based on that material, “Astronomy Methods” (2004) and “Astrophysics Processes” (2008), the latter which earned him the 2010 Chambliss Astronomical Writing Prize of the American Astronomical Society (AAS).
Son of a musician and academic
Born on Dec. 7, 1930, to Wilber and Norma Bradt in Colfax, Washington, he was raised in Washington State, as well as Maine, New York City, and Washington, where he graduated from high school.
His mother was a musician and writer, and his father was a chemistry professor at the University of Maine who served in the Army during World War II.
Six weeks after Bradt's father returned home from the war, he took his own life. Hale Bradt was 15. In 1980, Bradt discovered a stack of his father’s personal letters written during the war, which led to a decades-long research project that took him to the Pacific islands where his father served. This culminated with the book trilogy “Wilber’s War,” which earned him two silver awards from the IBPA’s Benjamin Franklin and Foreword Reviews’ IndieFAB; he was also an award finalist from National Indie Excellence.
Bradt discovered his love of music early; he sang in the Grace Church School choir in fifth and sixth grades, and studied the violin from the age of 8 until he was 21. He studied musicology and composition at Princeton University, where he played in the Princeton Orchestra. He also took weekly lessons in New York City with one of his childhood teachers, Irma Zacharias, who was the mother of MIT professor Jerrold Zacharias. “I did not work at the music courses very hard and thus did poorly,” he recalled.
In the 1960s, at MIT he played with a string quartet that included MIT mathematicians Michael Artin, Lou Howard, and Arthur Mattuck. Bradt and his wife, Dottie, also sang with the MIT Chorale Society from about 1961 to 1971, including a 1962 trip to Europe.
Well into his 80s, Bradt retained an interest in classical music, both as a violinist and as a singer, performing with diverse amateur choruses, orchestras, and chamber groups. At one point he played with the Belmont Community Orchestra, and sang with the Paul Madore Chorale in Salem. In retirement, he and his wife enjoyed chamber music, opera, and the Boston Symphony Orchestra.
In the Navy
In the summer before his senior year he began Naval training, which is where he discovered a talent for “mathematical-technical stuff,” he said. “I discovered that on quantitative topics, like navigation, I was much more facile than my fellow students. I could picture vector diagrams and gun mechanisms easily.”
He said he came back to Princeton “determined to get a major in physics,” but because that would involve adding a fifth year to his studies, “the dean wisely convinced me to get my degree in music, get my Navy commission, and serve my two years.” He graduated in 1952, trained for the Navy with the Reserve Officer Candidate program, and served in the U.S. Navy as a deck officer and navigator on the USS Diphda cargo ship during the Korean War.
MIT years
He returned to Princeton to work in the Cosmic Ray lab, and then joined MIT as a graduate student in 1955, working in Bruno Rossi’s Cosmic Ray Group as a research assistant. Recalled Bradt, “The group was small, with only a half-dozen faculty and a similar number of students. Sputnik was launched, and the group was soon involved in space experiments with rockets, balloons, and satellites.”
The beginnings of celestial X-ray and gamma-ray astronomy took root in Cambridge, Massachusetts, as did the exploration of interplanetary space. Bradt also worked under Bill Kraushaar, George Clark, and Herbert Bridge, and was soon joined by radio astronomers Alan Barrett and Bernard Burke, and theorist Phil Morrison.
While working on his PhD thesis on cosmic rays, he took his measuring equipment to an old cement mine in New York State, to study cosmic rays that had enough energy to get through the 30 feet of overhead rock.
As a professor, he studied extensive air showers with gamma-ray primaries (as low-mu showers) on Mt. Chacaltaya in Bolivia, and in 1966, he participated in a rocket experiment that led to a precise celestial location and optical identification of the first stellar X-ray source, Scorpius X-1.
“X-ray astronomy was sort of a surprise,” said Bradt. “Nobody really predicted that there should be sources of X-rays out there.”
His group studied X-rays originating from the Milky Way Galaxy by using data collected with rockets, balloons, and satellites. In 1967, he collaborated with NASA to design and launch sounding rockets from White Sands Missile Range, which would use specialized instruments to detect X-rays above Earth’s atmosphere.
Bradt was a senior participant or a principal investigator for instruments on the NASA X-ray astronomy satellite missions SAS-3 that launched in 1975, HEAO-1 in 1977, and RXTE in 1995.
All Sky Monitor and RXTE
In 1980, Bradt and his colleagues at MIT, Goddard Space Flight Center, and the University of California at San Diego began designing a satellite that would measure X-ray bursts and other phenomena on time scales from milliseconds to years. By 1995, the team launched RXTE.
Until 2001, Bradt was the principal investigator of RXTE’s All Sky Monitor, which scanned vast swaths of the sky during each orbit. When it was decommissioned in 2012, the RXTE provided a 16-year record of X-ray emissions from various celestial objects, including black holes and neutron stars. The 1969 sounding rocket experiment by Bradt’s group discovered X-ray pulsations from the Crab pulsar, which demonstrated that the X-ray and optical pulses from this distant neutron star arrived almost simultaneously, despite traveling through interstellar space for thousands of years.
He received NASA’s Exceptional Scientific Achievement Medal in 1978 for his contributions to the HEAO-1 mission and shared the 1999 Bruno Rossi Prize of the American Astronomical Society’s High Energy Astrophysics Division for his role with RXTE.
“Hale's work on precision timing of compact stars, and his role as an instrument PI on NASA's Rossi X-ray Timing Explorer played an important part in cultivating the entrepreneurial spirit in MIT's Center for Space Research, now the MIT Kavli Institute,” says Rob Simcoe, the Francis L. Friedman Professor of Physics and director of the MIT Kavli Institute for Astrophysics and Space Research.
Without Bradt’s persistence, the HEAO 1 and RXTE missions may not have launched, recalls Alan Levine PhD ’76, a principal research scientist at Kavli who was the project scientist for RXTE. “Hale had to skillfully negotiate to have his MIT team join together with a (non-MIT) team that had been competing for the opportunities to provide both experimental hardware and scientific mission guidance,” he says. “The A-3 experiment was eventually carried out as a joint project between MIT under Hale and Harvard/Smithsonian under Herbert (Herb) Gursky.”
“Hale had a strong personality,” recalls Levine. “When he wanted something to be done, he came on strong and it was difficult to refuse. Often it was quicker to do what he wanted rather than to say no, only to be asked several more times and have to make up excuses.”
“He was persistent,” agrees former student, Professor Emeritus Saul Rappaport PhD ’68. “If he had a suggestion, he never let up.”
Rappaport also recalls Bradt’s exacting nature. For example, for one sounding rocket flight at White Sands Missile Range, “Hale took it upon himself to be involved in every aspect of the rocket payload, including parts of it that were built by Goddard Space Flight Center — I think this annoyed the folks at GSFC,” recalls Rappaport. “He would be checking everything three times. There was a famous scene where he stuck his ear in the (compressed-air) jet to make sure that it went off, and there was a huge blast of air that he wasn’t quite expecting. It scared the hell out of everybody, and the Goddard people were, you know, a bit amused. The point is that he didn’t trust anything unless he could verify it himself.”
Supportive advisor
Many former students recalled Hale’s supportive teaching style, which included inviting MIT students over to their Belmont home, and was a strong advocate for his students’ professional development.
“He was a wonderful mentor: kind, generous, and encouraging,” recalls physics department head Professor Deepto Chakrabarty ’88, who had Bradt as his postdoctoral advisor when he returned to MIT in 1996.
“I’m so grateful to have had the chance to work with Hale as an undergraduate,” recalls University of California at Los Angeles professor and Nobel laureate Andrea Ghez ’87. “He taught me so much about high-energy astrophysics, the research world, and how to be a good mentor. Over the years, he continuously gave me new opportunities — starting with working on onboard data acquisition and data analysis modes for the future Rossi X-Ray Timing Explorer with Ed Morgan and Al Levine. Later, he introduced me to a project to do optical identification of X-ray sources, which began with observing with the MIT-Michigan-Dartmouth Telescope (MDM) with then-postdoc Meg Urry and him.”
Bradt was a relatively new professor when he became Saul Rappaport’s advisor in 1963. At the time, MIT researchers were switching from the study of cosmic rays to the new field of X-ray astronomy. “Hale turned the whole rocket program over to me as a relatively newly minted PhD, which was great for my career, and he went on to some satellite business, the SAS 3 satellite in particular. He was very good in terms of looking out for the careers of junior scientists with whom he was associated.”
Bradt looked back on his legacy at MIT physics with pride. “Today, the astrophysics division of the department is a thriving community of faculty, postdocs, and graduate students,” Bradt said recently. “I cast my lot with X-ray astronomy in 1966 and had a wonderfully exciting time observing the X-ray sky from space until my retirement in 2001.”
After retirement, Bradt served for 16 years as academic advisor for MIT’s McCormick Hall first-year students. He received MIT's Buechner Teaching Prize in Physics in 1990, Outstanding Freshman Advisor of the Year Award in 2004, and the Alan J. Lazarus (1953) Excellence in Advising Award in 2017.
Recalls Ghez, “He was a remarkable and generous mentor and helped me understand the importance of helping undergraduates make the transition from the classroom to the wonderfully enriching world of research.”
Post-retirement, Bradt transitioned into department historian and mentor.
“I arrived at MIT in 2003, and it was several years before I realized that Hale had actually retired two years earlier — he was frequently around, and always happy to talk with young researchers,” says Simcoe. “In his later years, Hale became an unofficial historian for CSR and MKI, providing firsthand accounts of important events and people central to MIT's contribution to the ‘space race’ of the mid-20th century, and explaining how we evolved into a major center for research and education in spaceflight and astrophysics.”
Bradt’s other recognitions include earning a 2015 Darius and Susan Anderson Distinguished Service Award of the Institute of Governmental Studies, a 1978 NASA Exceptional Scientific Achievement Medal, and being named a 1972 American Physical Society Fellow and 2020 AAS Legacy Fellow.
Bradt served as secretary-treasurer (1973–75) and chair (1981) of the AAS High Energy Astrophysics Division, and on the National Academy of Science’s Committee for Space Astronomy and Astrophysics from 1979 to 1982. He recruited many of his colleagues and students to help him host the 1989 meeting of the American Astronomical Society in Boston, a major astronomy conference.
The son of the late Lt. Col. Wilber E. Bradt and Norma Sparlin Bourjaily, and brother of the late Valerie Hymes of Annapolis, Maryland, he is survived by his wife, Dorothy Haughey Bradt, whom he married in 1958; two daughters and their husbands, Elizabeth Bradt and J. Bartlett “Bart” Hoskins of Salem, and Dorothy and Bart McCrum of Buxton, Maine; two grandchildren, Benjamin and Rebecca Hoskins; two other sisters, Abigail Campi of St. Michael’s, Maryland, and Dale Anne Bourjaily of the Netherlands, and 10 nieces and nephews.
In lieu of flowers, contributions may be made to the Salem Athenaeum, or the Thomas Fellowship. Hale established the Thomas Fellowship in memory of Barbara E. Thomas, who was the Department of Physics undergraduate administrator from 1931 to 1965, as well as to honor the support staff who have contributed to the department's teaching and research programs.
“MIT has provided a wonderful environment for me to teach and to carry out research,” said Bradt. “I am exceptionally grateful for that and happy to be in a position to give back.” He added, “Besides, I am told you cannot take it with you.”
The Barbara E. Thomas Fund in support of physics graduate students has been established in the Department of Physics. You may contribute to the fund (#3312250) online at the MIT website giving.mit.edu by selecting “Give Now,” then “Physics.”
Introducing MIT HEALS, a life sciences initiative to address pressing health challengesThe MIT Health and Life Sciences Collaborative will bring together researchers from across the Institute to deliver health care solutions at scale.At MIT, collaboration between researchers working in the life sciences and engineering is a frequent occurrence. Under a new initiative launched last week, the Institute plans to strengthen and expand those collaborations to take on some of the most pressing health challenges facing the world.
The new MIT Health and Life Sciences Collaborative, or MIT HEALS, will bring together researchers from all over the Institute to find new solutions to challenges in health care. HEALS will draw on MIT’s strengths in life sciences and other fields, including artificial intelligence and chemical and biological engineering, to accelerate progress in improving patient care.
“As a source of new knowledge, of new tools and new cures, and of the innovators and the innovations that will shape the future of biomedicine and health care, there is just no place like MIT,” MIT President Sally Kornbluth said at a launch event last Wednesday in Kresge Auditorium. “Our goal with MIT HEALS is to help inspire, accelerate, and deliver solutions, at scale, to some of society’s most urgent and intractable health challenges.”
The launch event served as a day-long review of MIT’s historical impact in the life sciences and a preview of what it hopes to accomplish in the future.
“The talent assembled here has produced some truly towering accomplishments. But also — and, I believe, more importantly — you represent a deep well of creative potential for even greater impact,” Kornbluth said.
Massachusetts Governor Maura Healey, who addressed the filled auditorium, spoke of her excitement about the new initiative, emphasizing that “MIT’s leadership and the work that you do are more important than ever.”
“One of things as governor that I really appreciate is the opportunity to see so many of our state’s accomplished scientists and bright minds come together, work together, and forge a new commitment to improving human life,” Healey said. “It’s even more exciting when you think about this convening to think about all the amazing cures and treatments and discoveries that will result from it. I’m proud to say, and I really believe this, this is something that could only happen in Massachusetts. There’s no place that has the ecosystem that we have here, and we must fight hard to always protect that and to nurture that.”
A history of impact
MIT has a long history of pioneering new fields in the life sciences, as MIT Institute Professor Phillip Sharp noted in his keynote address. Fifty years ago, MIT’s Center for Cancer Research was born, headed by Salvador Luria, a molecular biologist and a 1975 Nobel laureate.
That center helped to lead the revolutions in molecular biology, and later recombinant DNA technology, which have had significant impacts on human health. Research by MIT Professor Robert Weinberg and others identifying cancer genes has led the development of targeted drugs for cancer, including Herceptin and Gleevec.
In 2007, the Center for Cancer Research evolved into the Koch Institute for Integrative Cancer Research, whose faculty members are divided evenly between the School of Science and the School of Engineering, and where interdisciplinary collaboration is now the norm.
While MIT has long been a pioneer in this kind of collaborative health research, over the past several years, MIT’s visiting committees reported that there was potential to further enhance those collaborations, according to Nergis Mavalvala, dean of MIT’s School of Science.
“One of the very strong themes that emerged was that there’s an enormous hunger among our colleagues to collaborate more. And not just within their disciplines and within their departments, but across departmental boundaries, across school boundaries, and even with the hospitals and the biotech sector,” Mavalvala told MIT News.
To explore whether MIT could be doing more to encourage interdisciplinary research in the life sciences, Mavalvala and Anantha Chandrakasan, dean of the School of Engineering and MIT’s chief innovation and strategy officer, appointed a faculty committee called VITALS (Vision to Integrate, Translate and Advance Life Sciences).
That committee was co-chaired by Tyler Jacks, the David H. Koch Professor of Biology at MIT and a member and former director of the Koch Institute, and Kristala Jones Prather, head of MIT’s Department of Chemical Engineering.
“We surveyed the faculty, and for many people, the sense was that they could do more if there were improved mechanisms for interaction and collaboration. Not that those don’t exist — everybody knows that we have a highly collaborative environment at MIT, but that we could do even more if we had some additional infrastructure in place to facilitate bringing people together, and perhaps providing funding to initiate collaborative projects,” Jacks said before last week’s launch.
These efforts will build on and expand existing collaborative structures. MIT is already home to a number of institutes that promote collaboration across disciplines, including not only the Koch Institute but also the McGovern Institute for Brain Research, the Picower Institute for Learning and Memory, and the Institute for Medical Engineering and Science.
“We have some great examples of crosscutting work around MIT, but there's still more opportunity to bring together faculty and researchers across the Institute,” Chandrakasan said before the launch event. “While there are these great individual pieces, we can amplify those while creating new collaborations.”
Supporting science
In her opening remarks on Wednesday, Kornbluth announced several new programs designed to support researchers in the life sciences and help promote connections between faculty at MIT, surrounding institutions and hospitals, and companies in the Kendall Square area.
“A crucial part of MIT HEALS will be finding ways to support, mentor, connect, and foster community for the very best minds, at every stage of their careers,” she said.
With funding provided by Noubar Afeyan PhD ’87, an executive member of the MIT Corporation and founder and CEO of Flagship Pioneering, MIT HEALS will offer fellowships for graduate students interested in exploring new directions in the life sciences.
Another key component of MIT HEALS will be the new Hood Pediatric Innovation Hub, which will focus on development of medical treatments specifically for children. This program, established with a gift from the Charles H. Hood Foundation, will be led by Elazer Edelman, a cardiologist and the Edward J. Poitras Professor in Medical Engineering and Science at MIT.
“Currently, the major market incentives are for medical innovations intended for adults — because that’s where the money is. As a result, children are all too often treated with medical devices and therapies that don’t meet their needs, because they’re simply scaled-down versions of the adult models,” Kornbluth said.
As another tool to help promising research projects get off the ground, MIT HEALS will include a grant program known as the MIT-MGB Seed Program. This program, which will fund joint research projects between MIT and Massachusetts General Hospital/Brigham and Women’s Hospital, is being launched with support from Analog Devices, to establish the Analog Devices, Inc. Fund for Health and Life Sciences.
Additionally, the Biswas Family Foundation is providing funding for postdoctoral fellows, who will receive four-year appointments to pursue collaborative health sciences research. The details of the fellows program will be announced in spring 2025.
“One of the things we have learned through experience is that when we do collaborative work that is cross-disciplinary, the people who are actually crossing disciplinary boundaries and going into multiple labs are students and postdocs,” Mavalvala said prior to the launch event. “The trainees, the younger generation, are much more nimble, moving between labs, learning new techniques and integrating new ideas.”
Revolutions
Discussions following the release of the VITALS committee report identified seven potential research areas where new research could have a big impact: AI and life science, low-cost diagnostics, neuroscience and mental health, environmental life science, food and agriculture, the future of public health and health care, and women’s health. However, Chandrakasan noted that research within HEALS will not be limited to those topics.
“We want this to be a very bottom-up process,” he told MIT News. “While there will be a few areas like AI and life sciences that we will absolutely prioritize, there will be plenty of room for us to be surprised on those innovative, forward-looking directions, and we hope to be surprised.”
At the launch event, faculty members from departments across MIT shared their work during panels that focused on the biosphere, brains, health care, immunology, entrepreneurship, artificial intelligence, translation, and collaboration. In addition, a poster session highlighted over 100 research projects in areas such as diagnostics, women’s health, neuroscience, mental health, and more.
The program, which was developed by Amy Keating, head of the Department of Biology, and Katharina Ribbeck, the Andrew and Erna Viterbi Professor of Biological Engineering, also included a spoken-word performance by Victory Yinka-Banjo, an MIT senior majoring in computer science and molecular biology. In her performance, called “Systems,” Yinka-Banjo urged the audience to “zoom out,” look at systems in their entirety, and pursue collective action.
“To be at MIT is to contribute to an era of infinite impact. It is to look beyond the microscope, zooming out to embrace the grander scope. To be at MIT is to latch onto hope so that in spite of a global pandemic, we fight and we cope. We fight with science and policy across clinics, academia, and industry for the betterment of our planet, for our rights, for our health,” she said.
In a panel titled “Revolutions,” Douglas Lauffenburger, the Ford Professor of Engineering and one of the founders of MIT’s Department of Biological Engineering, noted that engineers have been innovating in medicine since the 1950s, producing critical advances such as kidney dialysis, prosthetic limbs, and sophisticated medical imaging techniques.
MIT launched its program in biological engineering in 1998, and it became a full-fledged department in 2005. The department was founded based on the concept of developing new approaches to studying biology and developing potential treatments based on the new advances being made in molecular biology and genomics.
“Those two revolutions laid the foundation for a brand new kind of engineering that was not possible before them,” Lauffenburger said.
During that panel, Jacks and Ruth Lehmann, director of the Whitehead Institute for Biomedical Research, outlined several interdisciplinary projects underway at the Koch Institute and the Whitehead Institute. Those projects include using AI to analyze mammogram images and detect cancer earlier, engineering drought-resistant plants, and using CRISPR to identify genes involved in toxoplasmosis infection.
These examples illustrate the potential impact that can occur when “basic science meets translational science,” Lehmann said.
“I’m really looking forward to HEALS further enlarging the interactions that we have, and I think the possibilities for science, both at a mechanistic level and understanding the complexities of health and the planet, are really great,” she said.
The importance of teamwork
To bring together faculty and students with common interests and help spur new collaborations, HEALS plans to host workshops on different health-related topics. A faculty committee is now searching for a director for HEALS, who will coordinate these efforts.
Another important goal of the HEALS initiative, which was the focus of the day’s final panel discussion, is enhancing partnerships with Boston-area hospitals and biotech companies.
“There are many, many different forms of collaboration,” said Anne Klibanski, president and CEO of Mass General Brigham. “Part of it is the people. You bring the people together. Part of it is the ideas. But I have found certainly in our system, the way to get the best and the brightest people working together is to give them a problem to solve. You give them a problem to solve, and that’s where you get the energy, the passion, and the talent working together.”
Robert Langer, the David H. Koch Institute Professor at MIT and a member of the Koch Institute, noted the importance of tackling fundamental challenges without knowing exactly where they will lead. Langer, trained as a chemical engineer, began working in biomedical research in the 1970s, when most of his engineering classmates were going into jobs in the oil industry.
At the time, he worked with Judah Folkman at Boston Children’s Hospital on the idea of developing drugs that would starve tumors by cutting off their blood supply. “It took many, many years before those would [reach patients],” he says. “It took Genentech doing great work, building on some of the things we did that would lead to Avastin and many other drugs.”
Langer has spent much of his career developing novel strategies for delivering molecules, including messenger RNA, into cells. In 2010, he and Afeyan co-founded Moderna to further develop mRNA technology, which was eventually incorporated into mRNA vaccines for Covid.
“The important thing is to try to figure out what the applications are, which is a team effort,” Langer said. “Certainly when we published those papers in 1976, we had obviously no idea that messenger RNA would be important, that Covid would even exist. And so really it ends up being a team effort over the years.”
MIT astronomers find the smallest asteroids ever detected in the main beltThe team’s detection method, which identified 138 space rocks ranging from bus- to stadium-sized, could aid in tracking potential asteroid impactors.The asteroid that extinguished the dinosaurs is estimated to have been about 10 kilometers across. That’s about as wide as Brooklyn, New York. Such a massive impactor is predicted to hit Earth rarely, once every 100 million to 500 million years.
In contrast, much smaller asteroids, about the size of a bus, can strike Earth more frequently, every few years. These “decameter” asteroids, measuring just tens of meters across, are more likely to escape the main asteroid belt and migrate in to become near-Earth objects. If they make impact, these small but mighty space rocks can send shockwaves through entire regions, such as the 1908 impact in Tunguska, Siberia, and the 2013 asteroid that broke up in the sky over Chelyabinsk, Urals. Being able to observe decameter main-belt asteroids would provide a window into the origin of meteorites.
Now, an international team led by physicists at MIT have found a way to spot the smallest decameter asteroids within the main asteroid belt — a rubble field between Mars and Jupiter where millions of asteroids orbit. Until now, the smallest asteroids that scientists were able to discern there were about a kilometer in diameter. With the team’s new approach, scientists can now spot asteroids in the main belt as small as 10 meters across.
In a paper appearing today in the journal Nature, the researchers report that they have used their approach to detect more than 100 new decameter asteroids in the main asteroid belt. The space rocks range from the size of a bus to several stadiums wide, and are the smallest asteroids within the main belt that have been detected to date.
The researchers envision that the approach can be used to identify and track asteroids that are likely to approach Earth.
“We have been able to detect near-Earth objects down to 10 meters in size when they are really close to Earth,” says the study’s lead author, Artem Burdanov, a research scientist in MIT’s Department of Earth, Atmospheric and Planetary Sciences. “We now have a way of spotting these small asteroids when they are much farther away, so we can do more precise orbital tracking, which is key for planetary defense.”
The study’s co-authors include MIT professors of planetary science Julien de Wit and Richard Binzel, along with collaborators from multiple other institutions, including the University of Liege in Belgium, Charles University in the Czech Republic, the European Space Agency, and institutions in Germany including Max Planck Institute for Extraterrestrial Physics, and the University of Oldenburg.
Image shift
De Wit and his team are primarily focused on searches and studies of exoplanets — worlds outside the solar system that may be habitable. The researchers are part of the group that in 2016 discovered a planetary system around TRAPPIST-1, a star that’s about 40 light years from Earth. Using the Transiting Planets and Planetismals Small Telescope (TRAPPIST) in Chile, the team confirmed that the star hosts rocky, Earth-sized planets, several of which are in the habitable zone.
Scientists have since trained many telescopes, focused at various wavelengths, on the TRAPPIST-1 system to further characterize the planets and look for signs of life. With these searches, astronomers have had to pick through the “noise” in telescope images, such as any gas, dust, and planetary objects between Earth and the star, to more clearly decipher the TRAPPIST-1 planets. Often, the noise they discard includes passing asteroids.
“For most astronomers, asteroids are sort of seen as the vermin of the sky, in the sense that they just cross your field of view and affect your data,” de Wit says.
De Wit and Burdanov wondered whether the same data used to search for exoplanets could be recycled and mined for asteroids in our own solar system. To do so, they looked to “shift and stack,” an image processing technique that was first developed in the 1990s. The method involves shifting multiple images of the same field of view and stacking the images to see whether an otherwise faint object can outshine the noise.
Applying this method to search for unknown asteroids in images that are originally focused on far-off stars would require significant computational resources, as it would involve testing a huge number of scenarios for where an asteroid might be. The researchers would then have to shift thousands of images for each scenario to see whether an asteroid is indeed where it was predicted to be.
Several years ago, Burdanov, de Wit, and MIT graduate student Samantha Hasler found they could do that using state-of-the-art graphics processing units that can process an enormous amount of imaging data at high speeds.
They initially tried their approach on data from the SPECULOOS (Search for habitable Planets EClipsing ULtra-cOOl Stars) survey — a system of ground-based telescopes that takes many images of a star over time. This effort, along with a second application using data from a telescope in Antarctica, showed that researchers could indeed spot a vast amount of new asteroids in the main belt.
“An unexplored space”
For the new study, the researchers looked for more asteroids, down to smaller sizes, using data from the world’s most powerful observatory — NASA’s James Webb Space Telescope (JWST), which is particularly sensitive to infrared rather than visible light. As it happens, asteroids that orbit in the main asteroid belt are much brighter at infrared wavelengths than at visible wavelengths, and thus are far easier to detect with JWST’s infrared capabilities.
The team applied their approach to JWST images of TRAPPIST-1. The data comprised more than 10,000 images of the star, which were originally obtained to search for signs of atmospheres around the system’s inner planets. After processing the images, the researchers were able to spot eight known asteroids in the main belt. They then looked further and discovered 138 new asteroids around the main belt, all within tens of meters in diameter — the smallest main belt asteroids detected to date. They suspect a few asteroids are on their way to becoming near-Earth objects, while one is likely a Trojan — an asteroid that trails Jupiter.
“We thought we would just detect a few new objects, but we detected so many more than expected, especially small ones,” de Wit says. “It is a sign that we are probing a new population regime, where many more small objects are formed through cascades of collisions that are very efficient at breaking down asteroids below roughly 100 meters.”
“Statistics of these decameter main belt asteroids are critical for modelling,” adds Miroslav Broz, co-author from the Prague Charles University in Czech Republic, and a specialist of the various asteroid populations in the solar system. “In fact, this is the debris ejected during collisions of bigger, kilometers-sized asteroids, which are observable and often exhibit similar orbits about the Sun, so that we group them into ‘families’ of asteroids.”
“This is a totally new, unexplored space we are entering, thanks to modern technologies,” Burdanov says. “It’s a good example of what we can do as a field when we look at the data differently. Sometimes there’s a big payoff, and this is one of them.”
This work was supported, in part, by the Heising-Simons Foundation, the Czech Science Foundation, and the NVIDIA Academic Hardware Grant Program.
Study: Browsing negative content online makes mental health struggles worseResearchers have developed a web plug-in to help those looking to protect their mental health make more informed decisions.People struggling with their mental health are more likely to browse negative content online, and in turn, that negative content makes their symptoms worse, according to a series of studies by researchers at MIT.
The group behind the research has developed a web plug-in tool to help those looking to protect their mental health make more informed decisions about the content they view.
The findings were outlined in an open-access paper by Tali Sharot, an adjunct professor of cognitive neurosciences at MIT and professor at University College London, and Christopher A. Kelly, a former visiting PhD student who was a member of Sharot’s Affective Brain Lab when the studies were conducted, who is now a postdoc at Stanford University’s Institute for Human Centered AI. The findings were published Nov. 21 in the journal Nature Human Behavior.
“Our study shows a causal, bidirectional relationship between health and what you do online. We found that people who already have mental health symptoms are more likely to go online and more likely to browse for information that ends up being negative or fearful,” Sharot says. “After browsing this content, their symptoms become worse. It is a feedback loop.”
The studies analyzed the web browsing habits of more than 1,000 participants by using natural language processing to calculate a negative score and a positive score for each web page visited, as well as scores for anger, fear, anticipation, trust, surprise, sadness, joy, and disgust. Participants also completed questionnaires to assess their mental health and indicated their mood directly before and after web-browsing sessions. The researchers found that participants expressed better moods after browsing less-negative web pages, and participants with worse pre-browsing moods tended to browse more-negative web pages.
In a subsequent study, participants were asked to read information from two web pages randomly selected from either six negative webpages or six neutral pages. They then indicated their mood levels both before and after viewing the pages. An analysis found that participants exposed to negative web pages reported to be in a worse mood than those who viewed neutral pages, and then subsequently visited more-negative pages when asked to browse the internet for 10 minutes.
“The results contribute to the ongoing debate regarding the relationship between mental health and online behavior,” the authors wrote. “Most research addressing this relationship has focused on the quantity of use, such as screen time or frequency of social media use, which has led to mixed conclusions. Here, instead, we focus on the type of content browsed and find that its affective properties are causally and bidirectionally related to mental health and mood.”
To test whether intervention could alter web-browsing choices and improve mood, the researchers provided participants with search engine results pages with three search results for each of several queries. Some participants were provided labels for each search result on a scale of “feel better” to “feel worse.” Other participants were not provided with any labels. Those who were provided with labels were less likely to choose negative content and more likely to choose positive content. A followup study found that those who viewed more positive content reported a significantly better mood.
Based on these findings, Sharot and Kelly created a downloadable plug-in tool called “Digital Diet” that offers scores for Google search results in three categories: emotion (whether people find the content positive or negative, on average), knowledge (to what extent information on a webpage helps people understand a topic, on average), and actionability (to what extent information on a webpage is useful on average). MIT electrical engineering and computer science graduate student Jonatan Fontanez '24, a former undergraduate researcher from MIT in Sharot’s lab, also contributed to the development of the tool. The tool was introduced publicly this week, along with the publication of the paper in Nature Human Behavior.
“People with worse mental health tend to seek out more-negative and fear-inducing content, which in turn exacerbates their symptoms, creating a vicious feedback loop,” Kelly says. “It is our hope that this tool can help them gain greater autonomy over what enters their minds and break negative cycles.”
The MIT K. Lisa Yang Center for Bionics and Sierra Leone’s Ministry of Health (MOH) have launched the first fully accredited educational program for prosthetists and orthotists in Sierra Leone.
Tens of thousands of people in Sierra Leone need orthotic braces and artificial limbs, but access to such specialized medical care in this African nation has been limited. On Nov. 7, the country’s inaugural class of future prosthetic and orthotic clinicians received their white coats at a ceremony in Sierra Leone’s National Rehabilitation Center, marking the start of their specialized training.
The agreement between the Yang Center and Sierra Leone’s MOH began last year with the signing of a detailed memorandum of understanding to strengthen the capabilities and services of that country’s orthotic and prosthetic (O&P) sector. The bionics center is part of the larger Yang Tan Collective at MIT, whose mission is to improve human well-being by accelerating science and engineering collaborations at a global scale.
The Sierra Leone initiative includes improvements across the supply chain for assistive technologies, clinic infrastructure and tools, technology translation pipelines, and education opportunities for Sierra Leoneans to expand local O&P capacity. The establishment of the new education and training program in Sierra Leone advances the collaboration’s shared goal to enable sustainable and independent operation of O&P services for the tens of thousands of citizens who live with physical disabilities due to amputation, poliomyelitis infection, or other causes.
Students in the program will receive their training through the Human Study School of Rehabilitation Sciences, a nongovernmental organization based in Germany whose training models have been used across 53 countries, including 15 countries in Africa.
“This White Coat Ceremony is an important milestone in our comprehensive strategy to transform care for persons with disabilities,” says Hugh Herr SM ’93, a professor of media arts and sciences at the MIT Media Lab and co-director of the K. Lisa Yang Center for Bionics at MIT, who has led the center's engagement with the MOH. “We are proud to introduce the first program in Sierra Leone to offer this type of clinical education, which will improve availability and access to prosthetic and orthotic health care across the nation.”
The ceremony featured a keynote address by the Honorable Chief Minister of Sierra Leone David Sengeh SM ’12, PhD ’16. Sengeh, a former graduate student of Herr’s research group and longtime advocate for a more inclusive Sierra Leone, has taken a personal interest in this collaboration.
“The government is very happy that this collaboration with the K. Lisa Yang Center for Bionics at MIT falls within our national development plan and our priorities,” says Sengeh. “Our goal is to invest in human capacity and strengthen systems for inclusion.”
Francesca Riccio-Ackerman, the graduate student lead for this project, adds that “this program has created opportunities for persons with disabilities to become clinicians that will treat others with the same condition, setting an example in inclusivity.”
The inaugural class of O&P students includes 11 men and women from across Sierra Leone who have undergone intensive preparatory training and passed a rigorous international standard entrance exam to earn their position in the program. The students are scheduled to complete their training in early 2027 and will have the opportunity to become certified as associate prosthetist/orthotists by the International Society for Prosthetics and Orthotics, the gold standard for professionals in the field.
The program utilizes a hybrid educational model developed by the Human Study School of Rehabilitation Sciences.
“Human Study's humanitarian education program is unique. We run the world’s only prosthetics and orthotics school that meets international standards at all three levels of the P&O profession,” says Chris Schlief, founder and CEO of Human Study. “We are delighted to be working with the Ministry of Health and MIT's K. Lisa Yang Center for Bionics to bring our training to Sierra Leone. Prosthetics and orthotics have an essential role to play in increasing mobility, dignity, and equality for people with disabilities. We are proud to be a partner in this groundbreaking program, training the first generation of P&O clinicians. This program will have an impact for generations to come.”
As for Sengeh, who authored the book, “Radical Inclusion: Seven Steps to Help You Create a More Just Workplace, Home, and World,” the new program in Sierra Leone embodies his vision for a more inclusive world. “Personally, as an MIT alumnus and chief minister of Sierra Leone, this is what true vision, action, and impact look like. As I often say, through Radical Inclusion #WeWillDeliver.”
Q&A: Transforming research through global collaborationsJosephine Carstensen and David McGee discuss the value and impact that MIT Global Seed Funds, which create synergistic partnerships between faculty and peers abroad, added to their research.The MIT Global Seed Funds (GSF) program fosters global research collaborations with MIT faculty and their peers abroad — creating partnerships that tackle complex global issues, from climate change to health-care challenges and beyond. Administered by the MIT Center for International Studies (CIS), the GSF program has awarded more than $26 million to over 1,200 faculty research projects since its inception in 2008. Through its unique funding structure — comprising a general fund for unrestricted geographical use and several specific funds within individual countries, regions, and universities — GSF supports a wide range of projects. The current call for proposals from MIT faculty and researchers with principal investigator status is open until Dec. 10.
CIS recently sat down with faculty recipients Josephine Carstensen and David McGee to discuss the value and impact GSF added to their research. Carstensen, the Gilbert W. Winslow Career Development Associate Professor of Civil and Environmental Engineering, generates computational designs for large-scale structures with the intent of designing novel low-carbon solutions. McGee, the William R. Kenan, Jr. Professor in the Department of Earth, Atmospheric and Planetary Sciences (EAPS), reconstructs the patterns, pace, and magnitudes of past hydro-climate changes.
Q: How did the Global Seed Funds program connect you with global partnerships related to your research?
Carstensen: One of the projects my lab is working on is to unlock the potential of complex cast-glass structures. Through our GSF partnership with researchers at TUDelft (Netherlands), my group was able to leverage our expertise in generative design algorithms alongside the TUDelft team, who are experts in the physical casting and fabrication of glass structures. Our initial connection to TUDelft was actually through one of my graduate students who was at a conference and met TUDelft researchers. He was inspired by their work and felt there could be synergy between our labs. The question then became: How do we connect with TUDelft? And that was what led us to the Global Seed Funds program.
McGee: Our research is based in fieldwork conducted in partnership with experts who have a rich understanding of local environments. These locations range from lake basins in Chile and Argentina to caves in northern Mexico, Vietnam, and Madagascar. GSF has been invaluable for helping foster partnerships with collaborators and universities in these different locations, enabling the pilot work and relationship-building necessary to establish longer-term, externally funded projects.
Q: Tell us more about your GSF-funded work.
Carstensen: In my research group at MIT, we live mainly in a computational regime, and we do very little proof-of-concept testing. To that point, we do not even have the facilities nor experience to physically build large-scale structures, or even specialized structures. GSF has enabled us to connect with the researchers at TUDelft who do much more experimental testing than we do. Being able to work with the experts at TUDelft within their physical realm provided valuable insights into their way of approaching problems. And, likewise, the researchers at TUDelft benefited from our expertise. It has been fruitful in ways we couldn’t have imagined within our lab at MIT.
McGee: The collaborative work supported by the GSF has focused on reconstructing how past climate changes impacted rainfall patterns around the world, using natural archives like lake sediments and cave formations. One particularly successful project has been our work in caves in northeastern Mexico, which has been conducted in partnership with researchers from the National Autonomous University of Mexico (UNAM) and a local caving group. This project has involved several MIT undergraduate and graduate students, sponsored a research symposium in Mexico City, and helped us obtain funding from the National Science Foundation for a longer-term project.
Q: You both mentioned the involvement of your graduate students. How exactly has the GSF augmented the research experience of your students?
Carstensen: The collaboration has especially benefited the graduate students from both the MIT and TUDelft teams. The opportunity presented through this project to engage in research at an international peer institution has been extremely beneficial for their academic growth and maturity. It has facilitated training in new and complementary technical areas that they would not have had otherwise and allowed them to engage with leading world experts. An example of this aspect of the project's success is that the collaboration has inspired one of my graduate students to actively pursue postdoc opportunities in Europe (including at TU Delft) after his graduation.
McGee: MIT students have traveled to caves in northeastern Mexico and to lake basins in northern Chile to conduct fieldwork and build connections with local collaborators. Samples enabled by GSF-supported projects became the focus of two graduate students’ PhD theses, two EAPS undergraduate senior theses, and multiple UROP [Undergraduate Research Opportunity Program] projects.
Q: Were there any unexpected benefits to the work funded by GSF?
Carstensen: The success of this project would not have been possible without this specific international collaboration. Both the Delft and MIT teams bring highly different essential expertise that has been necessary for the successful project outcome. It allowed both the Delft and MIT teams to gain an in-depth understanding of the expertise areas and resources of the other collaborators. Both teams have been deeply inspired. This partnership has fueled conversations about potential future projects and provided multiple outcomes, including a plan to publish two journal papers on the project outcome. The first invited publication is being finalized now.
McGee: GSF’s focus on reciprocal exchange has enabled external collaborators to spend time at MIT, sharing their work and exchanging ideas. Other funding is often focused on sending MIT researchers and students out, but GSF has helped us bring collaborators here, making the relationship more equal. A GSF-supported visit by Argentinian researchers last year made it possible for them to interact not just with my group, but with students and faculty across EAPS.
Troy Van Voorhis to step down as department head of chemistry Professor oversaw department growth, strengthened community, and developed outreach programs.Troy Van Voorhis, the Robert T. Haslam and Bradley Dewey Professor of Chemistry, will step down as department head of the Department of Chemistry at the end of this academic year. Van Voorhis has served as department head since 2019, previously serving the department as associate department head since 2015.
“Troy has been an invaluable partner and sounding board who could always be counted on for a wonderful mix of wisdom and pragmatism,” says Nergis Mavalvala, the Kathleen and Curtis Marble professor of astrophysics and dean of the MIT School of Science. “While department head, Troy provided calm guidance during the Covid pandemic, encouraging and financially supporting additional programs to improve his community’s quality of life.”
“I have had the pleasure of serving as head of our department for the past five-plus years. It has been a period of significant upheaval in our world,” says Van Voorhis. “Throughout it all, one of my consistent joys has been the privilege of working within the chemistry department and across the wider MIT community on research, education, and community building.”
Under Van Voorhis’ leadership, the Department of Chemistry implemented a department-wide statement of values that launched the Diversity, Equity, and Inclusion Committee, a Future Faculty Symposium that showcases rising stars in chemistry, and the Creating Bonds in Chemistry program that partners MIT faculty with chemistry faculty at select historically Black colleges and universities and minority-serving institutions.
Van Voorhis also oversaw a time of tremendous faculty growth in the department with the addition of nine new faculty. During his tenure as head, he also guided the department through a period of significant growth of interest in chemistry with the number of undergraduate majors, enrolled students, graduate students, and graduate student yields all up significantly.
Van Voorhis also had the honor of celebrating with the entire Institute for Professor Moungi Bawendi’s Nobel Prize in Chemistry — the department’s first win in 18 years, since Professor Richard R. Schrock’s win in 2005.
In addition to his service to the department within the School of Science, Van Voorhis had also co-chaired the Working Group on Curricula and Degrees for the MIT Stephen A. Schwarzman College of Computing. This service relates to Van Voorhis’ own research interests and programs.
Van Voorhis’ research lies at the nexus of chemistry and computation, and his work has impact on renewable energy and quantum computing. His lab is focused on developing new methods that provide an accurate description of electron dynamics in molecules and materials. Over the years, his research has led to advances in light-emitting diodes, solar cells, and other devices and technologies crucial to addressing 21st-century energy concerns.
Van Voorhis received his bachelor's degree in chemistry and mathematics from Rice University and his PhD in chemistry from the University of California at Berkeley in 2001. Following a postdoctoral fellowship at Harvard University, he joined the faculty of MIT in 2003 and was promoted to professor of chemistry in 2012.
He has received many honors and awards, including being named an Alfred P. Sloan research fellow, a fellow of the David and Lucille Packard Foundation, and a recipient of a National Science Foundation CAREER award. He has also received the MIT School of Science’s award for excellence in graduate teaching.
Is there enough land on Earth to fight climate change and feed the world?Study shows how smart policies could address competing land-use needs.Capping global warming at 1.5 degrees Celsius is a tall order. Achieving that goal will not only require a massive reduction in greenhouse gas emissions from human activities, but also a substantial reallocation of land to support that effort and sustain the biosphere, including humans. More land will be needed to accommodate a growing demand for bioenergy and nature-based carbon sequestration while ensuring sufficient acreage for food production and ecological sustainability.
The expanding role of land in a 1.5 C world will be twofold — to remove carbon dioxide from the atmosphere and to produce clean energy. Land-based carbon dioxide removal strategies include bioenergy with carbon capture and storage; direct air capture; and afforestation/reforestation and other nature-based solutions. Land-based clean energy production includes wind and solar farms and sustainable bioenergy cropland. Any decision to allocate more land for climate mitigation must also address competing needs for long-term food security and ecosystem health.
Land-based climate mitigation choices vary in terms of costs — amount of land required, implications for food security, impact on biodiversity and other ecosystem services — and benefits — potential for sequestering greenhouse gases and producing clean energy.
Now a study in the journal Frontiers in Environmental Science provides the most comprehensive analysis to date of competing land-use and technology options to limit global warming to 1.5 C. Led by researchers at the MIT Center for Sustainability Science and Strategy (CS3), the study applies the MIT Integrated Global System Modeling (IGSM) framework to evaluate costs and benefits of different land-based climate mitigation options in Sky2050, a 1.5 C climate-stabilization scenario developed by Shell.
Under this scenario, demand for bioenergy and natural carbon sinks increase along with the need for sustainable farming and food production. To determine if there’s enough land to meet all these growing demands, the research team uses current estimates of the Earth’s total habitable land area — about 11 billion hectares or 11 gigahectares (Gha), where a hectare is an area of 10,000 square meters or 2.471 acres — and land area used for food production and bioenergy (5 Gha), and assesses how these may change in the future.
The team finds that with transformative changes in policy, land management practices, and consumption patterns, global land is sufficient to provide a sustainable supply of food and ecosystem services throughout this century while also reducing greenhouse gas emissions in alignment with the 1.5 C goal. These transformative changes include policies to protect natural ecosystems; stop deforestation and accelerate reforestation and afforestation; promote advances in sustainable agriculture technology and practice; reduce agricultural and food waste; and incentivize consumers to purchase sustainably produced goods.
If such changes are implemented, 2.5–3.5 gha of land would be used for NBS practices to sequester 3–6 gigatonnes (Gt) of CO2 per year, and 0.4–0.6 gha of land would be allocated for energy production — 0.2–0.3 gha for bioenergy and 0.2–0.35 gha for wind and solar power generation.
“Our scenario shows that there is enough land to support a 1.5 degree C future as long as effective policies at national and global levels are in place,” says CS3 Principal Research Scientist Angelo Gurgel, the study’s lead author. “These policies must not only promote efficient use of land for food, energy, and nature, but also be supported by long-term commitments from government and industry decision-makers.”
The MIT Press releases report on the future of open access publishing and policyReport aims to “ensure that open science practices are sustainable and that they contribute to the highest quality research.”The MIT Press has released a comprehensive report that addresses how open access policies shape research and what is needed to maximize their positive impact on the research ecosystem.
The report, entitled “Access to Science and Scholarship 2024: Building an Evidence Base to Support the Future of Open Research Policy,” is the outcome of a National Science Foundation-funded workshop held at the Washington headquarters of the American Association for the Advancement of Science on Sept. 20.
While open access aims to democratize knowledge, its implementation has been a factor in the consolidation of the academic publishing industry, an explosion in published articles with inconsistent review and quality control, and new costs that may be hard for researchers and universities to bear, with less-affluent schools and regions facing the greatest risk. The workshop examined how open access and other open science policies may affect research and researchers in the future, how to measure their impact, and how to address emerging challenges.
The event brought together leading experts to discuss critical issues in open scientific and scholarly publishing. These issues include:
The report identifies key research questions in order to advance open science and scholarship. These include:
“This workshop report is a crucial step in building a data-driven roadmap for the future of open science publishing and policy,” says Phillip Sharp, Institute Professor and professor of biology emeritus at MIT, and faculty lead of the working group behind the workshop and the report. “By identifying key research questions around infrastructure, training, technology, and business models, we aim to ensure that open science practices are sustainable and that they contribute to the highest quality research.”
The full report is available for download, along with video recordings of the workshop.
The MIT Press is a leading academic publisher committed to advancing knowledge and innovation. It publishes significant books and journals across a wide range of disciplines spanning science, technology, design, humanities, and social science.
A blueprint for better cancer immunotherapiesBy examining antigen architectures, MIT researchers built a therapeutic cancer vaccine that may improve tumor response to immune checkpoint blockade treatments.Immune checkpoint blockade (ICB) therapies can be very effective against some cancers by helping the immune system recognize cancer cells that are masquerading as healthy cells.
T cells are built to recognize specific pathogens or cancer cells, which they identify from the short fragments of proteins presented on their surface. These fragments are often referred to as antigens. Healthy cells will will not have the same short fragments or antigens on their surface, and thus will be spared from attack.
Even with cancer-associated antigens studding their surfaces, tumor cells can still escape attack by presenting a checkpoint protein, which is built to turn off the T cell. Immune checkpoint blockade therapies bind to these “off-switch” proteins and allow the T cell to attack.
Researchers have established that how cancer-associated antigens are distributed throughout a tumor determines how it will respond to checkpoint therapies. Tumors with the same antigen signal across most of its cells respond well, but heterogeneous tumors with subpopulations of cells that each have different antigens, do not. The overwhelming majority of tumors fall into the latter category and are characterized by heterogenous antigen expression. Because the mechanisms behind antigen distribution and tumor response are poorly understood, efforts to improve ICB therapy response in heterogenous tumors have been hindered.
In a new study, MIT researchers analyzed antigen expression patterns and associated T cell responses to better understand why patients with heterogenous tumors respond poorly to ICB therapies. In addition to identifying specific antigen architectures that determine how immune systems respond to tumors, the team developed an RNA-based vaccine that, when combined with ICB therapies, was effective at controlling tumors in mouse models of lung cancer.
Stefani Spranger, associate professor of biology and member of MIT’s Koch Institute for Integrative Cancer Research, is the senior author of the study, appearing recently in the Journal for Immunotherapy of Cancer. Other contributors include Koch Institute colleague Forest White, the Ned C. (1949) and Janet Bemis Rice Professor and professor of biological engineering at MIT, and Darrell Irvine, professor of immunology and microbiology at Scripps Research Institute and a former member of the Koch Institute.
While RNA vaccines are being evaluated in clinical trials, current practice of antigen selection is based on the predicted stability of antigens on the surface of tumor cells.
“It’s not so black-and-white,” says Spranger. “Even antigens that don’t make the numerical cut-off could be really valuable targets. Instead of just focusing on the numbers, we need to look inside the complex interplays between antigen hierarchies to uncover new and important therapeutic strategies.”
Spranger and her team created mouse models of lung cancer with a number of different and well-defined expression patterns of cancer-associated antigens in order to analyze how each antigen impacts T cell response. They created both “clonal” tumors, with the same antigen expression pattern across cells, and “subclonal” tumors that represent a heterogenous mix of tumor cell subpopulations expressing different antigens. In each type of tumor, they tested different combinations of antigens with strong or weak binding affinity to MHC.
The researchers found that the keys to immune response were how widespread an antigen is expressed across a tumor, what other antigens are expressed at the same time, and the relative binding strength and other characteristics of antigens expressed by multiple cell populations in the tumor
As expected, mouse models with clonal tumors were able to mount an immune response sufficient to control tumor growth when treated with ICB therapy, no matter which combinations of weak or strong antigens were present. However, the team discovered that the relative strength of antigens present resulted in dynamics of competition and synergy between T cell populations, mediated by immune recognition specialists called cross-presenting dendritic cells in tumor-draining lymph nodes. In pairings of two weak or two strong antigens, one resulting T cell population would be reduced through competition. In pairings of weak and strong antigens, overall T cell response was enhanced.
In subclonal tumors, with different cell populations emitting different antigen signals, competition rather than synergy was the rule, regardless of antigen combination. Tumors with a subclonal cell population expressing a strong antigen would be well-controlled under ICB treatment at first, but eventually parts of the tumor lacking the strong antigen began to grow and developed the ability evade immune attack and resist ICB therapy.
Incorporating these insights, the researchers then designed an RNA-based vaccine to be delivered in combination with ICB treatment with the goal of strengthening immune responses suppressed by antigen-driven dynamics. Strikingly, they found that no matter the binding affinity or other characteristics of the antigen targeted, the vaccine-ICB therapy combination was able to control tumors in mouse models. The widespread availability of an antigen across tumor cells determined the vaccine’s success, even if that antigen was associated with weak immune response.
Analysis of clinical data across tumor types showed that the vaccine-ICB therapy combination may be an effective strategy for treating patients with tumors with high heterogeneity. Patterns of antigen architectures in patient tumors correlated with T cell synergy or competition in mice models and determined responsiveness to ICB in cancer patients. In future work with the Irvine laboratory at the Scripps Research Institute, the Spranger laboratory will further optimize the vaccine with the aim of testing the therapy strategy in the clinic.
Visualizing the potential impacts of a hurricane on people’s homes before it hits can help residents prepare and decide whether to evacuate.
MIT scientists have developed a method that generates satellite imagery from the future to depict how a region would look after a potential flooding event. The method combines a generative artificial intelligence model with a physics-based flood model to create realistic, birds-eye-view images of a region, showing where flooding is likely to occur given the strength of an oncoming storm.
As a test case, the team applied the method to Houston and generated satellite images depicting what certain locations around the city would look like after a storm comparable to Hurricane Harvey, which hit the region in 2017. The team compared these generated images with actual satellite images taken of the same regions after Harvey hit. They also compared AI-generated images that did not include a physics-based flood model.
The team’s physics-reinforced method generated satellite images of future flooding that were more realistic and accurate. The AI-only method, in contrast, generated images of flooding in places where flooding is not physically possible.
The team’s method is a proof-of-concept, meant to demonstrate a case in which generative AI models can generate realistic, trustworthy content when paired with a physics-based model. In order to apply the method to other regions to depict flooding from future storms, it will need to be trained on many more satellite images to learn how flooding would look in other regions.
“The idea is: One day, we could use this before a hurricane, where it provides an additional visualization layer for the public,” says Björn Lütjens, a postdoc in MIT’s Department of Earth, Atmospheric and Planetary Sciences, who led the research while he was a doctoral student in MIT’s Department of Aeronautics and Astronautics (AeroAstro). “One of the biggest challenges is encouraging people to evacuate when they are at risk. Maybe this could be another visualization to help increase that readiness.”
To illustrate the potential of the new method, which they have dubbed the “Earth Intelligence Engine,” the team has made it available as an online resource for others to try.
The researchers report their results today in the journal IEEE Transactions on Geoscience and Remote Sensing. The study’s MIT co-authors include Brandon Leshchinskiy; Aruna Sankaranarayanan; and Dava Newman, professor of AeroAstro and director of the MIT Media Lab; along with collaborators from multiple institutions.
Generative adversarial images
The new study is an extension of the team’s efforts to apply generative AI tools to visualize future climate scenarios.
“Providing a hyper-local perspective of climate seems to be the most effective way to communicate our scientific results,” says Newman, the study’s senior author. “People relate to their own zip code, their local environment where their family and friends live. Providing local climate simulations becomes intuitive, personal, and relatable.”
For this study, the authors use a conditional generative adversarial network, or GAN, a type of machine learning method that can generate realistic images using two competing, or “adversarial,” neural networks. The first “generator” network is trained on pairs of real data, such as satellite images before and after a hurricane. The second “discriminator” network is then trained to distinguish between the real satellite imagery and the one synthesized by the first network.
Each network automatically improves its performance based on feedback from the other network. The idea, then, is that such an adversarial push and pull should ultimately produce synthetic images that are indistinguishable from the real thing. Nevertheless, GANs can still produce “hallucinations,” or factually incorrect features in an otherwise realistic image that shouldn’t be there.
“Hallucinations can mislead viewers,” says Lütjens, who began to wonder whether such hallucinations could be avoided, such that generative AI tools can be trusted to help inform people, particularly in risk-sensitive scenarios. “We were thinking: How can we use these generative AI models in a climate-impact setting, where having trusted data sources is so important?”
Flood hallucinations
In their new work, the researchers considered a risk-sensitive scenario in which generative AI is tasked with creating satellite images of future flooding that could be trustworthy enough to inform decisions of how to prepare and potentially evacuate people out of harm’s way.
Typically, policymakers can get an idea of where flooding might occur based on visualizations in the form of color-coded maps. These maps are the final product of a pipeline of physical models that usually begins with a hurricane track model, which then feeds into a wind model that simulates the pattern and strength of winds over a local region. This is combined with a flood or storm surge model that forecasts how wind might push any nearby body of water onto land. A hydraulic model then maps out where flooding will occur based on the local flood infrastructure and generates a visual, color-coded map of flood elevations over a particular region.
“The question is: Can visualizations of satellite imagery add another level to this, that is a bit more tangible and emotionally engaging than a color-coded map of reds, yellows, and blues, while still being trustworthy?” Lütjens says.
The team first tested how generative AI alone would produce satellite images of future flooding. They trained a GAN on actual satellite images taken by satellites as they passed over Houston before and after Hurricane Harvey. When they tasked the generator to produce new flood images of the same regions, they found that the images resembled typical satellite imagery, but a closer look revealed hallucinations in some images, in the form of floods where flooding should not be possible (for instance, in locations at higher elevation).
To reduce hallucinations and increase the trustworthiness of the AI-generated images, the team paired the GAN with a physics-based flood model that incorporates real, physical parameters and phenomena, such as an approaching hurricane’s trajectory, storm surge, and flood patterns. With this physics-reinforced method, the team generated satellite images around Houston that depict the same flood extent, pixel by pixel, as forecasted by the flood model.
“We show a tangible way to combine machine learning with physics for a use case that’s risk-sensitive, which requires us to analyze the complexity of Earth’s systems and project future actions and possible scenarios to keep people out of harm’s way,” Newman says. “We can’t wait to get our generative AI tools into the hands of decision-makers at the local community level, which could make a significant difference and perhaps save lives.”
The research was supported, in part, by the MIT Portugal Program, the DAF-MIT Artificial Intelligence Accelerator, NASA, and Google Cloud.
A vision for U.S. science successIn a talk at MIT, White House science advisor Arati Prabhakar outlined challenges in medicine, climate, and AI, while expressing resolve to tackle hard problems.White House science advisor Arati Prabhakar expressed confidence in U.S. science and technology capacities during a talk on Wednesday about major issues the country must tackle.
“Let me start with the purpose of science and technology and innovation, which is to open possibilities so that we can achieve our great aspirations,” said Prabhakar, who is the director of the Office of Science and Technology Policy (OSTP) and a co-chair of the President’s Council of Advisors on Science and Technology (PCAST).
“The aspirations that we have as a country today are as great as they have ever been,” she added.
Much of Prabhakar’s talk focused on three major issues in science and technology development: cancer prevention, climate change, and AI. In the process, she also emphasized the necessity for the U.S. to sustain its global leadership in research across domains of science and technology, which she called “one of America’s long-time strengths.”
“Ever since the end of the Second World War, we said we’re going in on basic research, we’re going to build our universities’ capacity to do it, we have an unparalleled basic research capacity, and we should always have that,” said Prabhakar.
“We have gotten better, I think, in recent years at commercializing technology from our basic research,” Prabhakar added, noting, “Capital moves when you can see profit and growth.” The Biden administration, she said, has invested in a variety of new ways for the public and private sector to work together to massively accelerate the movement of technology into the market.
Wednesday’s talk drew a capacity audience of nearly 300 people in MIT’s Wong Auditorium and was hosted by the Manufacturing@MIT Working Group. The event included introductory remarks by Suzanne Berger, an Institute Professor and a longtime expert on the innovation economy, and Nergis Mavalvala, dean of the School of Science and an astrophysicist and leader in gravitational-wave detection.
Introducing Mavalvala, Berger said the 2015 announcement of the discovery of gravitational waves “was the day I felt proudest and most elated to be a member of the MIT community,” and noted that U.S. government support helped make the research possible. Mavalvala, in turn, said MIT was “especially honored” to hear Prabhakar discuss leading-edge research and acknowledge the role of universities in strengthening the country’s science and technology sectors.
Prabhakar has extensive experience in both government and the private sector. She has been OSTP director and co-chair of PCAST since October of 2022. She served as director of the Defense Advanced Research Projects Agency (DARPA) from 2012 to 2017 and director of the National Institute of Standards and Technology (NIST) from 1993 to 1997.
She has also held executive positions at Raychem and Interval Research, and spent a decade at the investment firm U.S. Venture Partners. An engineer by training, Prabhakar earned a BS in electrical engineering from Texas Tech University in 1979, an MA in electrical engineering from Caltech in 1980, and a PhD in applied physics from Caltech in 1984.
Among other remarks about medicine, Prabhakar touted the Biden administration’s “Cancer Moonshot” program, which aims to cut the cancer death rate in half over the next 25 years through multiple approaches, from better health care provision and cancer detection to limiting public exposure to carcinogens. We should be striving, Prabhakar said, for “a future in which people take good health for granted and can get on with their lives.”
On AI, she heralded both the promise and concerns about technology, saying, “I think it’s time for active steps to get on a path to where it actually allows people to do more and earn more.”
When it comes to climate change, Prabhakar said, “We all understand that the climate is going to change. But it’s in our hands how severe those changes get. And it’s possible that we can build a better future.” She noted the bipartisan infrastructure bill signed into law in 2021 and the Biden administration’s Inflation Reduction Act as important steps forward in this fight.
“Together those are making the single biggest investment anyone anywhere on the planet has ever made in the clean energy transition,” she said. “I used to feel hopeless about our ability to do that, and it gives me tremendous hope.”
After her talk, Prabhakar was joined onstage for a group discussion with the three co-presidents of the MIT Energy and Climate Club: Laurentiu Anton, a doctoral candidate in electrical engineering and computer science; Rosie Keller, an MBA candidate at the MIT Sloan School of Management; and Thomas Lee, a doctoral candidate in MIT’s Institute for Data, Systems, and Society.
Asked about the seemingly sagging public confidence in science today, Prabhakar offered a few thoughts.
“The first thing I would say is, don’t take it personally,” Prabhakar said, noting that any dip in public regard for science is less severe than the diminished public confidence in other institutions.
Adding some levity, she observed that in polling about which occupations are regarded as being desirable for a marriage partner to have, “scientist” still ranks highly.
“Scientists still do really well on that front, we’ve got that going for us,” she quipped.
More seriously, Prabhakar observed, rather than “preaching” at the public, scientists should recognize that “part of the job for us is to continue to be clear about what we know are the facts, and to present them clearly but humbly, and to be clear that we’re going to continue working to learn more.” At the same time, she continued, scientists can always reinforce that “oh, by the way, facts are helpful things that can actually help you make better choices about how the future turns out. I think that would be better in my view.”
Prabhakar said that her White House work had been guided, in part, by one of the overarching themes that President Biden has often reinforced.
“He thinks about America as a nation that can be described in a single word, and that word is ‘possibilities,’” she said. “And that idea, that is such a big idea, it lights me up. I think of what we do in the world of science and technology and innovation as really part and parcel of creating those possibilities.”
Ultimately, Prabhakar said, at all times and all points in American history, scientists and technologists must continue “to prove once more that when people come together and do this work … we do it in a way that builds opportunity and expands opportunity for everyone in our country. I think this is the great privilege we all have in the work we do, and it’s also our responsibility.”
3 Questions: Claire Wang on training the brain for memory sports The MIT sophomore and award-winning memory champion explains what these competitions are all about and why you might want to build a “memory palace.”On Nov. 10, some of the country’s top memorizers converged on MIT’s Kresge Auditorium to compete in a “Tournament of Memory Champions” in front of a live audience.
The competition was split into four events: long-term memory, words-to-remember, auditory memory, and double-deck of cards, in which competitors must memorize the exact order of two decks of cards. In between the events, MIT faculty who are experts in the science of memory provided short talks and demos about memory and how to improve it. Among the competitors was MIT’s own Claire Wang, a sophomore majoring in electrical engineering and computer science. Wang has competed in memory sports for years, a hobby that has taken her around the world to learn from some of the best memorists on the planet. At the tournament, she tied for first place in the words-to-remember competition.
The event commemorated the 25th anniversary of the USA Memory Championship Organization (USAMC). USAMC sponsored the event in partnership with MIT’s McGovern Institute for Brain Research, the Department of Brain and Cognitive Sciences, the MIT Quest for Intelligence, and the company Lumosity.
MIT News sat down with Wang to learn more about her experience with memory competitions — and see if she had any advice for those of us with less-than-amazing memory skills.
Q: How did you come to get involved in memory competitions?
A: When I was in middle school, I read the book “Moonwalking with Einstein,” which is about a journalist’s journey from average memory to being named memory champion in 2006. My parents were also obsessed with this TV show where people were memorizing decks of cards and performing other feats of memory. I had already known about the concept of “memory palaces,” so I was inspired to explore memory sports. Somehow, I convinced my parents to let me take a gap year after seventh grade, and I travelled the world going to competitions and learning from memory grandmasters. I got to know the community in that time and I got to build my memory system, which was really fun. I did a lot less of those competitions after that year and some subsequent competitions with the USA memory competition, but it’s still fun to have this ability.
Q: What was the Tournament of Memory Champions like?
A: USAMC invited a lot of winners from previous years to compete, which was really cool. It was nice seeing a lot of people I haven’t seen in years. I didn’t compete in every event because I was too busy to do the long-term memory, which takes you two weeks of memorization work. But it was a really cool experience. I helped a bit with the brainstorming beforehand because I know one of the professors running it. We thought about how to give the talks and structure the event.
Then I competed in the words event, which is when they give you 300 words over 15 minutes, and the competitors have to recall each one in order in a round robin competition. You got two strikes. A lot of other competitions just make you write the words down. The round robin makes it more fun for people to watch. I tied with someone else — I made a dumb mistake — so I was kind of sad in hindsight, but being tied for first is still great.
Since I hadn't done this in a while (and I was coming back from a trip where I didn’t get much sleep), I was a bit nervous that my brain wouldn’t be able to remember anything, and I was pleasantly surprised I didn’t just blank on stage. Also, since I hadn’t done this in a while, a lot of my loci and memory palaces were forgotten, so I had to speed-review them before the competition. The words event doesn’t get easier over time — it’s just 300 random words (which could range from “disappointment” to “chair”) and you just have to remember the order.
Q: What is your approach to improving memory?
A: The whole idea is that we memorize images, feelings, and emotions much better than numbers or random words. The way it works in practice is we make an ordered set of locations in a “memory palace.” The palace could be anything. It could be a campus or a classroom or a part of a room, but you imagine yourself walking through this space, so there’s a specific order to it, and in every location I place certain information. This is information related to what I’m trying to remember. I have pictures I associate with words and I have specific images I correlate with numbers. Once you have a correlated image system, all you need to remember is a story, and then when you recall, you translate that back to the original information.
Doing memory sports really helps you with visualization, and being able to visualize things faster and better helps you remember things better. You start remembering with spaced repetition that you can talk yourself through. Allowing things to have an emotional connection is also important, because you remember emotions better. Doing memory competitions made me want to study neuroscience and computer science at MIT.
The specific memory sports techniques are not as useful in everyday life as you’d think, because a lot of the information we learn is more operative and requires intuitive understanding, but I do think they help in some ways. First, sometimes you have to initially remember things before you can develop a strong intuition later. Also, since I have to get really good at telling a lot of stories over time, I have gotten great at visualization and manipulating objects in my mind, which helps a lot.
When a cell protector collaborates with a killerNew research reveals what it takes for a protein that is best known for protecting cells against death to take on the opposite role.From early development to old age, cell death is a part of life. Without enough of a critical type of cell death known as apoptosis, animals wind up with too many cells, which can set the stage for cancer or autoimmune disease. But careful control is essential, because when apoptosis eliminates the wrong cells, the effects can be just as dire, helping to drive many kinds of neurodegenerative disease.
By studying the microscopic roundworm Caenorhabditis elegans — which was honored with its fourth Nobel Prize last month — scientists at MIT’s McGovern Institute for Brain Research have begun to unravel a longstanding mystery about the factors that control apoptosis: how a protein capable of preventing programmed cell death can also promote it. Their study, led by Robert Horvitz, the David H. Koch Professor of Biology at MIT, and reported Oct. 9 in the journal Science Advances, sheds light on the process of cell death in both health and disease.
“These findings, by graduate student Nolan Tucker and former graduate student, now MIT faculty colleague, Peter Reddien, have revealed that a protein interaction long thought to block apoptosis in C. elegans likely instead has the opposite effect,” says Horvitz, who is also an investigator at the Howard Hughes Medical Institute and the McGovern Institute. Horvitz shared the 2002 Nobel Prize in Physiology or Medicine for discovering and characterizing the genes controlling cell death in C. elegans.
Mechanisms of cell death
Horvitz, Tucker, Reddien, and colleagues have provided foundational insights in the field of apoptosis by using C. elegans to analyze the mechanisms that drive apoptosis, as well as the mechanisms that determine how cells ensure apoptosis happens when and where it should. Unlike humans and other mammals, which depend on dozens of proteins to control apoptosis, these worms use just a few. And when things go awry, it’s easy to tell: When there’s not enough apoptosis, researchers can see that there are too many cells inside the worms’ translucent bodies. And when there’s too much, the worms lack certain biological functions or, in more extreme cases, can’t reproduce or die during embryonic development.
Work in the Horvitz lab defined the roles of many of the genes and proteins that control apoptosis in worms. These regulators proved to have counterparts in human cells, and for that reason studies of worms have helped reveal how human cells govern cell death and pointed toward potential targets for treating disease.
A protein’s dual role
Three of C. elegans’ primary regulators of apoptosis actively promote cell death, whereas just one, CED-9, reins in the apoptosis-promoting proteins to keep cells alive. As early as the 1990s, however, Horvitz and colleagues recognized that CED-9 was not exclusively a protector of cells. Their experiments indicated that the protector protein also plays a role in promoting cell death. But while researchers thought they knew how CED-9 protected against apoptosis, its pro-apoptotic role was more puzzling.
CED-9’s dual role means that mutations in the gene that encode it can impact apoptosis in multiple ways. Most ced-9 mutations interfere with the protein’s ability to protect against cell death and result in excess cell death. Conversely, mutations that abnormally activate ced-9 cause too little cell death, just like mutations that inactivate any of the three killer genes.
An atypical ced-9 mutation, identified by Reddien when he was a PhD student in Horvitz’s lab, hinted at how CED-9 promotes cell death. That mutation altered the part of the CED-9 protein that interacts with the protein CED-4, which is proapoptotic. Since the mutation specifically leads to a reduction in apoptosis, this suggested that CED-9 might need to interact with CED-4 to promote cell death.
The idea was particularly intriguing because researchers had long thought that CED-9’s interaction with CED-4 had exactly the opposite effect: In the canonical model, CED-9 anchors CED-4 to cells’ mitochondria, sequestering the CED-4 killer protein and preventing it from associating with and activating another key killer, the CED-3 protein — thereby preventing apoptosis.
To test the hypothesis that CED-9’s interactions with the killer CED-4 protein enhance apoptosis, the team needed more evidence. So graduate student Nolan Tucker used CRISPR gene editing tools to create more worms with mutations in CED-9, each one targeting a different spot in the CED-4-binding region. Then he examined the worms. “What I saw with this particular class of mutations was extra cells and viability,” he says — clear signs that the altered CED-9 was still protecting against cell death, but could no longer promote it. “Those observations strongly supported the hypothesis that the ability to bind CED-4 is needed for the pro-apoptotic function of CED-9,” Tucker explains. Their observations also suggested that, contrary to earlier thinking, CED-9 doesn’t need to bind with CED-4 to protect against apoptosis.
When he looked inside the cells of the mutant worms, Tucker found additional evidence that these mutations prevented CED-9’s ability to interact with CED-4. When both CED-9 and CED-4 are intact, CED-4 appears associated with cells’ mitochondria. But in the presence of these mutations, CED-4 was instead at the edge of the cell nucleus. CED-9’s ability to bind CED-4 to mitochondria appeared to be necessary to promote apoptosis, not to protect against it.
Looking ahead
While the team’s findings begin to explain a long-unanswered question about one of the primary regulators of apoptosis, they raise new ones, as well. “I think that this main pathway of apoptosis has been seen by a lot of people as more-or-less settled science. Our findings should change that view,” Tucker says.
The researchers see important parallels between their findings from this study of worms and what’s known about cell death pathways in mammals. The mammalian counterpart to CED-9 is a protein called BCL-2, mutations in which can lead to cancer. BCL-2, like CED-9, can both promote and protect against apoptosis. As with CED-9, the pro-apoptotic function of BCL-2 has been mysterious. In mammals, too, mitochondria play a key role in activating apoptosis. The Horvitz lab’s discovery opens opportunities to better understand how apoptosis is regulated not only in worms but also in humans, and how dysregulation of apoptosis in humans can lead to such disorders as cancer, autoimmune disease, and neurodegeneration.
MIT physicists predict exotic form of matter with potential for quantum computingNew work suggests the ability to create fractionalized electrons known as non-Abelian anyons without a magnetic field, opening new possibilities for basic research and future applications.MIT physicists have shown that it should be possible to create an exotic form of matter that could be manipulated to form the qubit (quantum bit) building blocks of future quantum computers that are even more powerful than the quantum computers in development today.
The work builds on a discovery last year of materials that host electrons that can split into fractions of themselves but, importantly, can do so without the application of a magnetic field.
The general phenomenon of electron fractionalization was first discovered in 1982 and resulted in a Nobel Prize. That work, however, required the application of a magnetic field. The ability to create the fractionalized electrons without a magnetic field opens new possibilities for basic research and makes the materials hosting them more useful for applications.
When electrons split into fractions of themselves, those fractions are known as anyons. Anyons come in variety of flavors, or classes. The anyons discovered in the 2023 materials are known as Abelian anyons. Now, in a paper reported in the Oct. 17 issue of Physical Review Letters, the MIT team notes that it should be possible to create the most exotic class of anyons, non-Abelian anyons.
“Non-Abelian anyons have the bewildering capacity of ‘remembering’ their spacetime trajectories; this memory effect can be useful for quantum computing,” says Liang Fu, a professor in MIT’s Department of Physics and leader of the work.
Fu further notes that “the 2023 experiments on electron fractionalization greatly exceeded theoretical expectations. My takeaway is that we theorists should be bolder.”
Fu is also affiliated with the MIT Materials Research Laboratory. His colleagues on the current work are graduate students Aidan P. Reddy and Nisarga Paul, and postdoc Ahmed Abouelkomsan, all of the MIT Department of Phsyics. Reddy and Paul are co-first authors of the Physical Review Letters paper.
The MIT work and two related studies were also featured in an Oct. 17 story in Physics Magazine. “If this prediction is confirmed experimentally, it could lead to more reliable quantum computers that can execute a wider range of tasks … Theorists have already devised ways to harness non-Abelian states as workable qubits and manipulate the excitations of these states to enable robust quantum computation,” writes Ryan Wilkinson.
The current work was guided by recent advances in 2D materials, or those consisting of only one or a few layers of atoms. “The whole world of two-dimensional materials is very interesting because you can stack them and twist them, and sort of play Legos with them to get all sorts of cool sandwich structures with unusual properties,” says Paul. Those sandwich structures, in turn, are called moiré materials.
Anyons can only form in two-dimensional materials. Could they form in moiré materials? The 2023 experiments were the first to show that they can. Soon afterwards, a group led by Long Ju, an MIT assistant professor of physics, reported evidence of anyons in another moiré material. (Fu and Reddy were also involved in the Ju work.)
In the current work, the physicists showed that it should be possible to create non-Abelian anyons in a moiré material composed of atomically thin layers of molybdenum ditelluride. Says Paul, “moiré materials have already revealed fascinating phases of matter in recent years, and our work shows that non-Abelian phases could be added to the list.”
Adds Reddy, “our work shows that when electrons are added at a density of 3/2 or 5/2 per unit cell, they can organize into an intriguing quantum state that hosts non-Abelian anyons.”
The work was exciting, says Reddy, in part because “oftentimes there’s subtlety in interpreting your results and what they are actually telling you. So it was fun to think through our arguments” in support of non-Abelian anyons.
Says Paul, “this project ranged from really concrete numerical calculations to pretty abstract theory and connected the two. I learned a lot from my collaborators about some very interesting topics.”
This work was supported by the U.S. Air Force Office of Scientific Research. The authors also acknowledge the MIT SuperCloud and Lincoln Laboratory Supercomputing Center, the Kavli Institute for Theoretical Physics, the Knut and Alice Wallenberg Foundation, and the Simons Foundation.
How can electrons split into fractions of themselves?Physicists surprised to discover electrons in pentalayer graphene can exhibit fractional charge. New study suggests how this could work.MIT physicists have taken a key step toward solving the puzzle of what leads electrons to split into fractions of themselves. Their solution sheds light on the conditions that give rise to exotic electronic states in graphene and other two-dimensional systems.
The new work is an effort to make sense of a discovery that was reported earlier this year by a different group of physicists at MIT, led by Assistant Professor Long Ju. Ju’s team found that electrons appear to exhibit “fractional charge” in pentalayer graphene — a configuration of five graphene layers that are stacked atop a similarly structured sheet of boron nitride.
Ju discovered that when he sent an electric current through the pentalayer structure, the electrons seemed to pass through as fractions of their total charge, even in the absence of a magnetic field. Scientists had already shown that electrons can split into fractions under a very strong magnetic field, in what is known as the fractional quantum Hall effect. Ju’s work was the first to find that this effect was possible in graphene without a magnetic field — which until recently was not expected to exhibit such an effect.
The phenemonon was coined the “fractional quantum anomalous Hall effect,” and theorists have been keen to find an explanation for how fractional charge can emerge from pentalayer graphene.
The new study, led by MIT professor of physics Senthil Todadri, provides a crucial piece of the answer. Through calculations of quantum mechanical interactions, he and his colleagues show that the electrons form a sort of crystal structure, the properties of which are ideal for fractions of electrons to emerge.
“This is a completely new mechanism, meaning in the decades-long history, people have never had a system go toward these kinds of fractional electron phenomena,” Todadri says. “It’s really exciting because it makes possible all kinds of new experiments that previously one could only dream about.”
The team’s study appeared last week in the journal Physical Review Letters. Two other research teams — one from Johns Hopkins University, and the other from Harvard University, the University of California at Berkeley, and Lawrence Berkeley National Laboratory — have each published similar results in the same issue. The MIT team includes Zhihuan Dong PhD ’24 and former postdoc Adarsh Patri.
“Fractional phenomena”
In 2018, MIT professor of physics Pablo Jarillo-Herrero and his colleagues were the first to observe that new electronic behavior could emerge from stacking and twisting two sheets of graphene. Each layer of graphene is as thin as a single atom and structured in a chicken-wire lattice of hexagonal carbon atoms. By stacking two sheets at a very specific angle to each other, he found that the resulting interference, or moiré pattern, induced unexpected phenomena such as both superconducting and insulating properties in the same material. This “magic-angle graphene,” as it was soon coined, ignited a new field known as twistronics, the study of electronic behavior in twisted, two-dimensional materials.
“Shortly after his experiments, we realized these moiré systems would be ideal platforms in general to find the kinds of conditions that enable these fractional electron phases to emerge,” says Todadri, who collaborated with Jarillo-Herrero on a study that same year to show that, in theory, such twisted systems could exhibit fractional charge without a magnetic field. “We were advocating these as the best systems to look for these kinds of fractional phenomena,” he says.
Then, in September of 2023, Todadri hopped on a Zoom call with Ju, who was familiar with Todari’s theoretical work and had kept in touch with him through Ju’s own experimental work.
“He called me on a Saturday and showed me the data in which he saw these [electron] fractions in pentalayer graphene,” Todadri recalls. “And that was a big surprise because it didn’t play out the way we thought.”
In his 2018 paper, Todadri predicted that fractional charge should emerge from a precursor phase characterized by a particular twisting of the electron wavefunction. Broadly speaking, he theorized that an electron’s quantum properties should have a certain twisting, or degree to which it can be manipulated without changing its inherent structure. This winding, he predicted, should increase with the number of graphene layers added to a given moiré structure.
“For pentalayer graphene, we thought the wavefunction would wind around five times, and that would be a precursor for electron fractions,” Todadri says. “But he did his experiments and discovered that it does wind around, but only once. That then raised this big question: How should we think about whatever we are seeing?”
Extraordinary crystal
In the team’s new study, Todadri went back to work out how electron fractions could emerge from pentalayer graphene if not through the path he initially predicted. The physicists looked through their original hypothesis and realized they may have missed a key ingredient.
“The standard strategy in the field when figuring out what’s happening in any electronic system is to treat electrons as independent actors, and from that, figure out their topology, or winding,” Todadri explains. “But from Long’s experiments, we knew this approximation must be incorrect.”
While in most materials, electrons have plenty of space to repel each other and zing about as independent agents, the particles are much more confined in two-dimensional structures such as pentalayer graphene. In such tight quarters, the team realized that electrons should also be forced to interact, behaving according to their quantum correlations in addition to their natural repulsion. When the physicists added interelectron interactions to their theory, they found it correctly predicted the winding that Ju observed for pentalayer graphene.
Once they had a theoretical prediction that matched with observations, the team could work from this prediction to identify a mechanism by which pentalayer graphene gave rise to fractional charge.
They found that the moiré arrangement of pentalayer graphene, in which each lattice-like layer of carbon atoms is arranged atop the other and on top of the boron-nitride, induces a weak electrical potential. When electrons pass through this potential, they form a sort of crystal, or a periodic formation, that confines the electrons and forces them to interact through their quantum correlations. This electron tug-of-war creates a sort of cloud of possible physical states for each electron, which interacts with every other electron cloud in the crystal, in a wavefunction, or a pattern of quantum correlations, that gives the winding that should set the stage for electrons to split into fractions of themselves.
“This crystal has a whole set of unusual properties that are different from ordinary crystals, and leads to many fascinating questions for future research,” Todadri says. “For the short term, this mechanism provides the theoretical foundation for understanding the observations of fractions of electrons in pentalayer graphene and for predicting other systems with similar physics.”
This work was supported, in part, by the National Science Foundation and the Simons Foundation.
Four from MIT named 2025 Rhodes ScholarsYiming Chen ’24, Wilhem Hector, Anushka Nair, and David Oluigbo will start postgraduate studies at Oxford next fall.Yiming Chen ’24, Wilhem Hector, Anushka Nair, and David Oluigbo have been selected as 2025 Rhodes Scholars and will begin fully funded postgraduate studies at Oxford University in the U.K. next fall. In addition to MIT’s two U.S. Rhodes winners, Oluigbo and Nair, two affiliates were awarded international Rhodes Scholarships: Chen for Rhodes’ China constituency and Hector for the Global Rhodes Scholarship. Hector is the first Haitian citizen to be named a Rhodes Scholar.
The scholars were supported by Associate Dean Kim Benard and the Distinguished Fellowships team in Career Advising and Professional Development. They received additional mentorship and guidance from the Presidential Committee on Distinguished Fellowships.
“It is profoundly inspiring to work with our amazing students, who have accomplished so much at MIT and, at the same time, thought deeply about how they can have an impact in solving the world's major challenges,” says Professor Nancy Kanwisher, who co-chairs the committee along with Professor Tom Levenson. “These students have worked hard to develop and articulate their vision and to learn to communicate it to others with passion, clarity, and confidence. We are thrilled but not surprised to see so many of them recognized this year as finalists and as winners.”
Yiming Chen ’24
Yiming Chen, from Beijing, China, and the Washington area, was named one of four Rhodes China Scholars on Sept 28. At Oxford, she will pursue graduate studies in engineering science, working toward her ongoing goal of advancing AI safety and reliability in clinical workflows.
Chen graduated from MIT in 2024 with a BS in mathematics and computer science and an MEng in computer science. She worked on several projects involving machine learning for health care, and focused her master’s research on medical imaging in the Medical Vision Group of the Computer Science and Artificial Intelligence Laboratory (CSAIL).
Collaborating with IBM Research, Chen developed a neural framework for clinical-grade lumen segmentation in intravascular ultrasound and presented her findings at the MICCAI Machine Learning in Medical Imaging conference. Additionally, she worked at Cleanlab, an MIT-founded startup, creating an open-source library to ensure the integrity of image datasets used in vision tasks.
Chen was a teaching assistant in the MIT math and electrical engineering and computer science departments, and received a teaching excellence award. She taught high school students at the Hampshire College Summer Studies in Math and was selected to participate in MISTI Global Teaching Labs in Italy.
Having studied the guzheng, a traditional Chinese instrument, since age 4, Chen served as president of the MIT Chinese Music Ensemble, explored Eastern and Western music synergies with the MIT Chamber Music Society, and performed at the United Nations. On campus, she was also active with Asymptones a capella, MIT Ring Committee, Ribotones, Figure Skating Club, and the Undergraduate Association Innovation Committee.
Wilhem Hector
Wilhem Hector, a senior from Port-au-Prince, Haiti, majoring in mechanical engineering, was awarded a Global Rhodes Scholarship on Nov 1. The first Haitian national to be named a Rhodes Scholar, Hector will pursue at Oxford a master’s in energy systems followed by a master’s in education, focusing on digital and social change. His long-term goals are twofold: pioneering Haiti’s renewable energy infrastructure and expanding hands-on opportunities in the country‘s national curriculum.
Hector developed his passion for energy through his research in the MIT Howland Lab, where he investigated the uncertainty of wind power production during active yaw control. He also helped launch the MIT Renewable Energy Clinic through his work on the sources of opposition to energy projects in the U.S. Beyond his research, Hector had notable contributions as an intern at Radia Inc. and DTU Wind Energy Systems, where he helped develop computational wind farm modeling and simulation techniques.
Outside of MIT, he leads the Hector Foundation, a nonprofit providing educational opportunities to young people in Haiti. He has raised over $80,000 in the past five years to finance their initiatives, including the construction of Project Manus, Haiti’s first open-use engineering makerspace. Hector’s service endeavors have been supported by the MIT PKG Center, which awarded him the Davis Peace Prize, the PKG Fellowship for Social Impact, and the PKG Award for Public Service.
Hector co-chairs both the Student Events Board and the Class of 2025 Senior Ball Committee and has served as the social chair for Chocolate City and the African Students Association.
Anushka Nair
Anushka Nair, from Portland, Oregon, will graduate next spring with BS and MEng degrees in computer science and engineering with concentrations in economics and AI. She plans to pursue a DPhil in social data science at the Oxford Internet Institute. Nair aims to develop ethical AI technologies that address pressing societal challenges, beginning with combating misinformation.
For her master’s thesis under Professor David Rand, Nair is developing LLM-powered fact-checking tools to detect nuanced misinformation beyond human or automated capabilities. She also researches human-AI co-reasoning at the MIT Center for Collective Intelligence with Professor Thomas Malone. Previously, she conducted research on autonomous vehicle navigation at Stanford’s AI and Robotics Lab, energy microgrid load balancing at MIT’s Institute for Data, Systems, and Society, and worked with Professor Esther Duflo in economics.
Nair interned in the Executive Office of the Secretary General at the United Nations, where she integrated technology solutions and assisted with launching the High-Level Advisory Body on AI. She also interned in Tesla’s energy sector, contributing to Autobidder, an energy trading tool, and led the launch of a platform for monitoring distributed energy resources and renewable power plants. Her work has earned her recognition as a Social and Ethical Responsibilities of Computing Scholar and a U.S. Presidential Scholar.
Nair has served as President of the MIT Society of Women Engineers and MIT and Harvard Women in AI, spearheading outreach programs to mentor young women in STEM fields. She also served as president of MIT Honors Societies Eta Kappa Nu and Tau Beta Pi.
David Oluigbo
David Oluigbo, from Washington, is a senior majoring in artificial intelligence and decision making and minoring in brain and cognitive sciences. At Oxford, he will undertake an MS in applied digital health followed by an MS in modeling for global health. Afterward, Oluigbo plans to attend medical school with the goal of becoming a physician-scientist who researches and applies AI to address medical challenges in low-income countries.
Since his first year at MIT, Oluigbo has conducted neural and brain research with Ev Fedorenko at the McGovern Institute for Brain Research and with Susanna Mierau’s Synapse and Network Development Group at Brigham and Women’s Hospital. His work with Mierau led to several publications and a poster presentation at the Federation of European Societies annual meeting.
In a summer internship at the National Institutes of Health Clinical Center, Oluigbo designed and trained machine-learning models on CT scans for automatic detection of neuroendocrine tumors, leading to first authorship on an International Society for Optics and Photonics conference proceeding paper, which he presented at the 2024 annual meeting. Oluigbo also did a summer internship with the Anyscale Learning for All Laboratory at the MIT Computer Science and Artificial Intelligence Laboratory.
Oluigbo is an EMT and systems administrator officer with MIT-EMS. He is a consultant for Code for Good, a representative on the MIT Schwarzman College of Computing Undergraduate Advisory Group, and holds executive roles with the Undergraduate Association, the MIT Brain and Cognitive Society, and the MIT Running Club.
Neuroscientists create a comprehensive map of the cerebral cortexUsing fMRI, the research team identified 24 networks that perform specific functions within the brain’s cerebral cortex.By analyzing brain scans taken as people watched movie clips, MIT researchers have created the most comprehensive map yet of the functions of the brain’s cerebral cortex.
Using functional magnetic resonance imaging (fMRI) data, the research team identified 24 networks with different functions, which include processing language, social interactions, visual features, and other types of sensory input.
Many of these networks have been seen before but haven’t been precisely characterized using naturalistic conditions. While the new study mapped networks in subjects watching engaging movies, previous works have used a small number of specific tasks or examined correlations across the brain in subjects who were simply resting.
“There’s an emerging approach in neuroscience to look at brain networks under more naturalistic conditions. This is a new approach that reveals something different from conventional approaches in neuroimaging,” says Robert Desimone, director of MIT’s McGovern Institute for Brain Research. “It’s not going to give us all the answers, but it generates a lot of interesting ideas based on what we see going on in the movies that's related to these network maps that emerge.”
The researchers hope that their new map will serve as a starting point for further study of what each of these networks is doing in the brain.
Desimone and John Duncan, a program leader in the MRC Cognition and Brain Sciences Unit at Cambridge University, are the senior authors of the study, which appears today in Neuron. Reza Rajimehr, a research scientist in the McGovern Institute and a former graduate student at Cambridge University, is the lead author of the paper.
Precise mapping
The cerebral cortex of the brain contains regions devoted to processing different types of sensory information, including visual and auditory input. Over the past few decades, scientists have identified many networks that are involved in this kind of processing, often using fMRI to measure brain activity as subjects perform a single task such as looking at faces.
In other studies, researchers have scanned people’s brains as they do nothing, or let their minds wander. From those studies, researchers have identified networks such as the default mode network, a network of areas that is active during internally focused activities such as daydreaming.
“Up to now, most studies of networks were based on doing functional MRI in the resting-state condition. Based on those studies, we know some main networks in the cortex. Each of them is responsible for a specific cognitive function, and they have been highly influential in the neuroimaging field,” Rajimehr says.
However, during the resting state, many parts of the cortex may not be active at all. To gain a more comprehensive picture of what all these regions are doing, the MIT team analyzed data recorded while subjects performed a more natural task: watching a movie.
“By using a rich stimulus like a movie, we can drive many regions of the cortex very efficiently. For example, sensory regions will be active to process different features of the movie, and high-level areas will be active to extract semantic information and contextual information,” Rajimehr says. “By activating the brain in this way, now we can distinguish different areas or different networks based on their activation patterns.”
The data for this study was generated as part of the Human Connectome Project. Using a 7-Tesla MRI scanner, which offers higher resolution than a typical MRI scanner, brain activity was imaged in 176 people as they watched one hour of movie clips showing a variety of scenes.
The MIT team used a machine-learning algorithm to analyze the activity patterns of each brain region, allowing them to identify 24 networks with different activity patterns and functions.
Some of these networks are located in sensory areas such as the visual cortex or auditory cortex, as expected for regions with specific sensory functions. Other areas respond to features such as actions, language, or social interactions. Many of these networks have been seen before, but this technique offers more precise definition of where the networks are located, the researchers say.
“Different regions are competing with each other for processing specific features, so when you map each function in isolation, you may get a slightly larger network because it is not getting constrained by other processes,” Rajimehr says. “But here, because all the areas are considered together, we are able to define more precise boundaries between different networks.”
The researchers also identified networks that hadn’t been seen before, including one in the prefrontal cortex, which appears to be highly responsive to visual scenes. This network was most active in response to pictures of scenes within the movie frames.
Executive control networks
Three of the networks found in this study are involved in “executive control,” and were most active during transitions between different clips. The researchers also observed that these control networks appear to have a “push-pull” relationship with networks that process specific features such as faces or actions. When networks specific to a particular feature were very active, the executive control networks were mostly quiet, and vice versa.
“Whenever the activations in domain-specific areas are high, it looks like there is no need for the engagement of these high-level networks,” Rajimehr says. “But in situations where perhaps there is some ambiguity and complexity in the stimulus, and there is a need for the involvement of the executive control networks, then we see that these networks become highly active.”
Using a movie-watching paradigm, the researchers are now studying some of the networks they identified in more detail, to identify subregions involved in particular tasks. For example, within the social processing network, they have found regions that are specific to processing social information about faces and bodies. In a new network that analyzes visual scenes, they have identified regions involved in processing memory of places.
“This kind of experiment is really about generating hypotheses for how the cerebral cortex is functionally organized. Networks that emerge during movie watching now need to be followed up with more specific experiments to test the hypotheses. It’s giving us a new view into the operation of the entire cortex during a more naturalistic task than just sitting at rest,” Desimone says.
The research was funded by the McGovern Institute, the Cognitive Science and Technology Council of Iran, the MRC Cognition and Brain Sciences Unit at the University of Cambridge, and a Cambridge Trust scholarship.
Asteroid grains shed light on the outer solar system’s originsA weak magnetic field likely pulled matter inward to form the outer planetary bodies, from Jupiter to Neptune.Tiny grains from a distant asteroid are revealing clues to the magnetic forces that shaped the far reaches of the solar system over 4.6 billion years ago.
Scientists at MIT and elsewhere have analyzed particles of the asteroid Ryugu, which were collected by the Japanese Aerospace Exploration Agency’s (JAXA) Hayabusa2 mission and brought back to Earth in 2020. Scientists believe Ryugu formed on the outskirts of the early solar system before migrating in toward the asteroid belt, eventually settling into an orbit between Earth and Mars.
The team analyzed Ryugu’s particles for signs of any ancient magnetic field that might have been present when the asteroid first took shape. Their results suggest that if there was a magnetic field, it would have been very weak. At most, such a field would have been about 15 microtesla. (The Earth’s own magnetic field today is around 50 microtesla.)
Even so, the scientists estimate that such a low-grade field intensity would have been enough to pull together primordial gas and dust to form the outer solar system’s asteroids and potentially play a role in giant planet formation, from Jupiter to Neptune.
The team’s results, which are published today in the journal AGU Advances, show for the first time that the distal solar system likely harbored a weak magnetic field. Scientists have known that a magnetic field shaped the inner solar system, where Earth and the terrestrial planets were formed. But it was unclear whether such a magnetic influence extended into more remote regions, until now.
“We’re showing that, everywhere we look now, there was some sort of magnetic field that was responsible for bringing mass to where the sun and planets were forming,” says study author Benjamin Weiss, the Robert R. Shrock Professor of Earth and Planetary Sciences at MIT. “That now applies to the outer solar system planets.”
The study’s lead author is Elias Mansbach PhD ’24, who is now a postdoc at Cambridge University. MIT co-authors include Eduardo Lima, Saverio Cambioni, and Jodie Ream, along with Michael Sowell and Joseph Kirschvink of Caltech, Roger Fu of Harvard University, Xue-Ning Bai of Tsinghua University, Chisato Anai and Atsuko Kobayashi of the Kochi Advanced Marine Core Research Institute, and Hironori Hidaka of Tokyo Institute of Technology.
A far-off field
Around 4.6 billion years ago, the solar system formed from a dense cloud of interstellar gas and dust, which collapsed into a swirling disk of matter. Most of this material gravitated toward the center of the disk to form the sun. The remaining bits formed a solar nebula of swirling, ionized gas. Scientists suspect that interactions between the newly formed sun and the ionized disk generated a magnetic field that threaded through the nebula, helping to drive accretion and pull matter inward to form the planets, asteroids, and moons.
“This nebular field disappeared around 3 to 4 million years after the solar system’s formation, and we are fascinated with how it played a role in early planetary formation,” Mansbach says.
Scientists previously determined that a magnetic field was present throughout the inner solar system — a region that spanned from the sun to about 7 astronomical units (AU), out to where Jupiter is today. (One AU is the distance between the sun and the Earth.) The intensity of this inner nebular field was somewhere between 50 to 200 microtesla, and it likely influenced the formation of the inner terrestrial planets. Such estimates of the early magnetic field are based on meteorites that landed on Earth and are thought to have originated in the inner nebula.
“But how far this magnetic field extended, and what role it played in more distal regions, is still uncertain because there haven’t been many samples that could tell us about the outer solar system,” Mansbach says.
Rewinding the tape
The team got an opportunity to analyze samples from the outer solar system with Ryugu, an asteroid that is thought to have formed in the early outer solar system, beyond 7 AU, and was eventually brought into orbit near the Earth. In December 2020, JAXA’s Hayabusa2 mission returned samples of the asteroid to Earth, giving scientists a first look at a potential relic of the early distal solar system.
The researchers acquired several grains of the returned samples, each about a millimeter in size. They placed the particles in a magnetometer — an instrument in Weiss’ lab that measures the strength and direction of a sample’s magnetization. They then applied an alternating magnetic field to progressively demagnetize each sample.
“Like a tape recorder, we are slowly rewinding the sample’s magnetic record,” Mansbach explains. “We then look for consistent trends that tell us if it formed in a magnetic field.”
They determined that the samples held no clear sign of a preserved magnetic field. This suggests that either there was no nebular field present in the outer solar system where the asteroid first formed, or the field was so weak that it was not recorded in the asteroid’s grains. If the latter is the case, the team estimates such a weak field would have been no more than 15 microtesla in intensity.
The researchers also reexamined data from previously studied meteorites. They specifically looked at “ungrouped carbonaceous chondrites” — meteorites that have properties that are characteristic of having formed in the distal solar system. Scientists had estimated the samples were not old enough to have formed before the solar nebula disappeared. Any magnetic field record the samples contain, then, would not reflect the nebular field. But Mansbach and his colleagues decided to take a closer look.
“We reanalyzed the ages of these samples and found they are closer to the start of the solar system than previously thought,” Mansbach says. “We think these samples formed in this distal, outer region. And one of these samples does actually have a positive field detection of about 5 microtesla, which is consistent with an upper limit of 15 microtesla.”
This updated sample, combined with the new Ryugu particles, suggest that the outer solar system, beyond 7 AU, hosted a very weak magnetic field, that was nevertheless strong enough to pull matter in from the outskirts to eventually form the outer planetary bodies, from Jupiter to Neptune.
“When you’re further from the sun, a weak magnetic field goes a long way,” Weiss notes. “It was predicted that it doesn’t need to be that strong out there, and that’s what we’re seeing.”
The team plans to look for more evidence of distal nebular fields with samples from another far-off asteroid, Bennu, which were delivered to Earth in September 2023 by NASA’s OSIRIS-REx spacecraft.
“Bennu looks a lot like Ryugu, and we’re eagerly awaiting first results from those samples,” Mansbach says.
This research was supported, in part, by NASA.
A portable light system that can digitize everyday objectsA new design tool uses UV and RGB lights to change the color and textures of everyday objects. The system could enable surfaces to display dynamic patterns, such as health data and fashion designs.When Nikola Tesla predicted we’d have handheld phones that could display videos, photographs, and more, his musings seemed like a distant dream. Nearly 100 years later, smartphones are like an extra appendage for many of us.
Digital fabrication engineers are now working toward expanding the display capabilities of other everyday objects. One avenue they’re exploring is reprogrammable surfaces — or items whose appearances we can digitally alter — to help users present important information, such as health statistics, as well as new designs on things like a wall, mug, or shoe.
Researchers from MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL), the University of California at Berkeley, and Aarhus University have taken an intriguing step forward by fabricating “PortaChrome,” a portable light system and design tool that can change the color and textures of various objects. Equipped with ultraviolet (UV) and red, green, and blue (RGB) LEDs, the device can be attached to everyday objects like shirts and headphones. Once a user creates a design and sends it to a PortaChrome machine via Bluetooth, the surface can be programmed into multicolor displays of health data, entertainment, and fashion designs.
To make an item reprogrammable, the object must be coated with photochromic dye, an invisible ink that can be turned into different colors with light patterns. Once it’s coated, individuals can create and relay patterns to the item via the team’s graphic design software, or use the team’s API to interact with the device directly and embed data-driven designs. When attached to a surface, PortaChrome’s UV lights saturate the dye while the RGB LEDs desaturate it, activating the colors and ensuring each pixel is toned to match the intended design.
Zhu and her colleagues’ integrated light system changes objects’ colors in less than four minutes on average, which is eight times faster than their prior work, “Photo-Chromeleon.” This speed boost comes from switching to a light source that makes contact with the object to transmit UV and RGB rays. Photo-Chromeleon used a projector to help activate the color-changing properties of photochromic dye, where the light on the object's surface is at a reduced intensity.
“PortaChrome provides a more convenient way to reprogram your surroundings,” says Yunyi Zhu ’20, MEng ’21, an MIT PhD student in electrical engineering and computer science, affiliate of CSAIL, and lead author on a paper about the work. “Compared with our projector-based system from before, PortaChrome is a more portable light source that can be placed directly on top of the photochromic surface. This allows the color change to happen without user intervention and helps us avoid contaminating our environment with UV. As a result, users can wear their heart rate chart on their shirt after a workout, for instance.”
Giving everyday objects a makeover
In demos, PortaChrome displayed health data on different surfaces. A user hiked with PortaChrome sewed onto their backpack, putting it into direct contact with the back of their shirt, which was coated in photochromic dye. Altitude and heart rate sensors sent data to the lighting device, which was then converted into a chart through a reprogramming script developed by the researchers. This process created a health visualization on the back of the user’s shirt. In a similar showing, MIT researchers displayed a heart gradually coming together on the back of a tablet to show how a user was progressing toward a fitness goal.
PortaChrome also showed a flair for customizing wearables. For example, the researchers redesigned some white headphones with sideways blue lines and horizontal yellow and purple stripes. The photochromic dye was coated on the headphones and the team then attached the PortaChrome device to the inside of the headphone case. Finally, the researchers successfully reprogrammed their patterns onto the object, which resembled watercolor art. Researchers also recolored a wrist splint to match different clothes using this process.
Eventually, the work could be used to digitize consumers’ belongings. Imagine putting on a cloak that can change your entire shirt design, or using your car cover to give your vehicle a new look.
PortaChrome’s main ingredients
On the hardware end, PortaChrome is a combination of four main ingredients. Their portable device consists of a textile base as a sort of backbone, a textile layer with the UV lights soldered on and another with the RGB stuck on, and a silicone diffusion layer to top it off. Resembling a translucent honeycomb, the silicone layer covers the interlaced UV and RGB LEDs and directs them toward individual pixels to properly illuminate a design over a surface.
This device can be flexibly wrapped around objects with different shapes. For tables and other flat surfaces, you could place PortaChrome on top, like a placemat. For a curved item like a thermos, you could wrap the light source around like a coffee cup sleeve to ensure it reprograms the entire surface.
The portable, flexible light system is crafted with maker space-available tools (like laser cutters, for example), and the same method can be replicated with flexible PCB materials and other mass manufacturing systems.
While it can also quickly convert our surroundings into dynamic displays, Zhu and her colleagues believe it could benefit from further speed boosts. They'd like to use smaller LEDs, with the likely result being a surface that could be reprogrammed in seconds with a higher-resolution design, thanks to increased light intensity.
“The surfaces of our everyday things are encoded with colors and visual textures, delivering crucial information and shaping how we interact with them,” says Georgia Tech postdoc Tingyu Cheng, who was not involved with the research. “PortaChrome is taking a leap forward by providing reprogrammable surfaces with the integration of flexible light sources (UV and RGB LEDs) and photochromic pigments into everyday objects, pixelating the environment with dynamic color and patterns. The capabilities demonstrated by PortaChrome could revolutionize the way we interact with our surroundings, particularly in domains like personalized fashion and adaptive user interfaces. This technology enables real-time customization that seamlessly integrates into daily life, offering a glimpse into the future of ‘ubiquitous displays.’”
Zhu is joined by nine CSAIL affiliates on the paper: MIT PhD student and MIT Media Lab affiliate Cedric Honnet; former visiting undergraduate researchers Yixiao Kang, Angelina J. Zheng, and Grace Tang; MIT undergraduate student Luca Musk; University of Michigan Assistant Professor Junyi Zhu SM ’19, PhD ’24; recent postdoc and Aarhus University assistant professor Michael Wessely; and senior author Stefanie Mueller, the TIBCO Career Development Associate Professor in the MIT departments of Electrical Engineering and Computer Science and Mechanical Engineering and leader of the HCI Engineering Group at CSAIL.
This work was supported by the MIT-GIST Joint Research Program and was presented at the ACM Symposium on User Interface Software and Technology in October.
A new MIT initiative aims to elevate human-centered research and teaching, and bring together scholars in the humanities, arts, and social sciences with their colleagues across the Institute.
The MIT Human Insight Collaborative (MITHIC) launched earlier this fall. A formal kickoff event for MITHIC was held on campus Monday, Oct. 28, before a full audience in MIT’s Huntington Hall (Room 10-250). The event featured a conversation with Min Jin Lee, acclaimed author of “Pachinko,” moderated by Linda Pizzuti Henry SM ’05, co-owner and CEO of Boston Globe Media.
Initiative leaders say MITHIC will foster creativity, inquiry, and understanding, amplifying the Institute’s impact on global challenges like climate change, AI, pandemics, poverty, democracy, and more.
President Sally Kornbluth says MITHIC is the first of a new model known as the MIT Collaboratives, designed among other things to foster and support new collaborations on compelling global problems. The next MIT Collaborative will focus on life sciences and health.
“The MIT Collaboratives will make it easier for our faculty to ‘go big’ — to pursue the most innovative ideas in their disciplines and build connections to other fields,” says Kornbluth.
“We created MITHIC with a particular focus on the human-centered fields, to help advance research with the potential for global impact. MITHIC also has another, more local aim: to support faculty in developing fresh approaches to teaching and research that will engage and inspire a new generation of students,” Kornbluth adds.
A transformative opportunity
MITHIC is co-chaired by Anantha Chandrakasan, chief innovation and strategy officer, dean of the School of Engineering, and the Vannevar Bush Professor of Electrical Engineering and Computer Science; and Agustin Rayo, Kenan Sahin Dean of the School of Humanities, Arts, and Social Sciences (SHASS).
“MITHIC is an incredibly exciting and meaningful initiative to me as it represents MIT at its core — bringing broad perspectives and human insights to solve some of the world’s most important problems,” says Chandrakasan. “It offers the opportunity to shape the future of research and education at MIT through advancing core scholarship in the individual humanities, arts, and social sciences disciplines, but also through cross-cutting problem formulation and problem-solving. I have no doubt MITHIC will inspire our community to think differently and work together in ways that will have a lasting impact on society.”
Rayo says true innovation must go beyond technology to encompass the full complexity of the human experience.
“At MIT, we aim to make the world a better place. But you can't make the world a better place unless you understand its full economic, political, social, ethical — human — dimensions,” Rayo says. “MITHIC can help ensure that MIT educates broad-minded students, who are ready for the multidimensional challenges of the future.”
Rayo sees MITHIC as a transformative opportunity for MIT.
“MIT needs an integrated approach, which combines STEM with the human-centered disciplines. MITHIC can help catalyze that integration,” he says.
Mark Gorenberg ’76, chair of the MIT Corporation, says MITHIC represents a commitment to collaboration, a spirit of curiosity, and the belief that uniting the humanities and sciences results in solutions that are not only innovative, but meaningful and lasting.
“MIT has long been a place where boundless ideas and entrepreneurial energy come together to meet the world’s toughest challenges,” Gorenberg says. “With MITHIC, we’re adding a powerful new layer to that mission — one that captures the richness of human experience and imagination.”
Support for MITHIC comes from all five MIT schools, the MIT Schwarzman College of Computing, and the Office of the Provost, along with philanthropic support.
Charlene Kabcenell ’79, a life member of the MIT Corporation, and Derry Kabcenell ’75 chose to support MITHIC financially.
“MIT produces world-class scientists and technologists, but expertise in the skills of these areas is not enough. We are excited that the collaborations catalyzed by this initiative will help our graduates to stay mindful of the impact of their work on people and society,” they say.
Ray Stata ’57, MIT Corporation life member emeritus, is also a benefactor of MITHIC.
“In industry, it is not just technical innovation and breakthroughs that win, but also culture, in the ways people collaborate and work together. These are skills and behaviors that can be learned through a deeper understanding of humanities and social sciences. This has always been an important part of MIT’s education and I am happy to see the renewed attention being given to this aspect of the learning experience,” he says.
“A potential game changer”
Keeril Makan, associate dean for strategic initiatives in SHASS and the Michael (1949) and Sonja Koerner Music Composition Professor, is the faculty lead for MITHIC.
“MITHIC is about incentivizing collaboration, not research in specific areas,” says Makan. “It’s a ground-up approach, where we support faculty based upon the research that is of interest to them, which they identify.”
MITHIC consists of three new funding opportunities for faculty, the largest of which is the SHASS+ Connectivity Fund. For all three funds, proposals can be for projects ready to begin, as well as planning grants in preparation for future proposals.
The SHASS+ Connectivity Fund will support research that bridges between SHASS fields and other fields at MIT. Proposals require a project lead in SHASS and another project lead whose primary appointment is outside of SHASS.
The SHASS+ Connectivity Fund is co-chaired by David Kaiser, the Germehausen Professor of the History of Science and professor of physics, and Maria Yang, deputy dean of engineering and Kendall Rohsenow Professor of Mechanical Engineering.
“MIT has set an ambitious agenda for itself focused on addressing extremely complex and challenging problems facing society today, such as climate change, and there is a critical role for technological solutions to address these problems,” Yang says. “However, the origin of these problems are in part due to humans, so humanistic considerations need to be part of the solution. Such problems cannot be conquered by technology alone.”
Yang says the goal of the SHASS+ Connectivity Fund is to enhance MIT’s research by building interdisciplinary teams, embedding a human-centered focus.
“My hope is that these collaborations will build bridges between SHASS and the rest of MIT, and will lead to integrated research that is more powerful and meaningful together,” says Yang.
Proposals for the first round of projects are due Nov. 22, but MITHIC is already bringing MIT faculty together to share ideas in hopes of sparking ideas for potential collaboration.
An information session and networking reception was held in September. MITHIC has also been hosting a series of “Meeting of the Minds” events. Makan says these have been opportunities for faculty and teaching staff to make connections around a specific topic or area of interest with colleagues they haven’t previously worked with.
Recent Meeting of the Minds sessions have been held on topics like cybersecurity, social history of math, food security, and rebuilding Ukraine.
“Faculty are already educating each other about their disciplines,” says Makan. “What happens in SHASS has been opaque to faculty in the other schools, just as the research in the other schools has been opaque to the faculty in SHASS. We’ve seen progress with initiatives like the Social and Ethical Responsibilities of Computing (SERC), when it comes to computing. MITHIC will broaden that scope.”
The leadership of MITHIC is cross-disciplinary, with a steering committee of faculty representing all five schools and the MIT Schwarzman College of Computing.
Iain Cheeseman, the Herman and Margaret Sokol Professor of Biology, is a member of the MITHIC steering committee. He says that while he continues to be amazed and inspired by the diverse research and work from across MIT, there’s potential to go even further by working together and connecting across diverse perspectives, ideas, and approaches.
“The bold goal and mission of MITHIC, to connect the humanities at MIT to work being conducted across the other schools at MIT, feels like a potential game-changer,” he says. “I am really excited to see the unexpected new work and directions that come out of this initiative, including hopefully connections that persist and transform the work across MIT.”
Enhancing the arts and humanities
In addition to the SHASS+ Connectivity Fund, MITHIC has two funds aimed specifically at enhancing research and teaching within SHASS.
The Humanities Cultivation Fund will support projects from the humanities and arts in SHASS. It is co-chaired by Arthur Bahr, professor of literature, and Anne McCants, the Ann F. Friedlaender Professor of History and SHASS research chair.
“Humanistic scholarship and artistic creation have long been among MIT’s hidden gems. The Humanities Cultivation Fund offers an exciting new opportunity to not only allow such work to continue to flourish, but also to give it greater visibility across the MIT community and into the wider world of scholarship. The fund aspires to cultivate — that is, to seed and nurture — new ideas and modes of inquiry into the full spectrum of human culture and expression,” says McCants.
The SHASS Education Innovation Fund will support new educational approaches in SHASS fields. The fund is co-chaired by Eric Klopfer, professor of comparative media studies/writing, and Emily Richmond Pollock, associate professor of music and SHASS undergraduate education chair.
Pollock says the fund is a welcome chance to support colleagues who have a strong sense of where teaching in SHASS could go next.
“We are looking for efforts that address contemporary challenges of teaching and learning, with approaches that can be tested in a specific context and later applied across the school. The crucial role of SHASS in educating MIT students in all fields means that what we devise here in our curriculum can have huge benefits for the Institute as a whole.”
Makan says infusing MIT’s human-centered disciplines with support is an essential part of MITHIC.
“The stronger these units are, the more the human-centered disciplines permeate the student experience, ultimately helping to build a stronger, more inclusive MIT,” says Makan.
Bridging Talents and Opportunities Forum connects high school and college students with STEAM leaders and resourcesEvent at MIT featured an array of national and international speakers including a Nobel laureate, leaders in industry, and in entertainment.Bridging Talents and Opportunities (BTO) held its second annual forum at the Stratton Student Center at MIT Oct. 11-12. The two-day event gathered over 500 participants, including high school students and their families, undergraduate students, professors, and leaders across STEAM (science, technology, engineering, arts, and mathematics) fields.
The forum sought to empower talented students from across the United States and Latin America to dream big and pursue higher education, demonstrating that access to prestigious institutions like MIT is possible regardless of socioeconomic barriers. The event featured inspirational talks from world-renowned scientists, innovators, entrepreneurs, social leaders, and major figures in entertainment — from Nobel laureate Rigoberta Menchú Tum to musician and producer Emilio Estefan, and more.
“Our initiative is committed to building meaningful connections among talented young individuals, their families, foundations, and leaders in science, art, mathematics, and technology,” says Ronald Garcia Ruiz, the Thomas A. Frank Career Development Assistant Professor of Physics at MIT and an organizer of the forum. “Recognizing that talent is universal but opportunities are often confined to select sectors of society, we are dedicated to bridging this gap. BTO provides a platform for sharing inspiring stories and offering support to promising young talents, empowering them to seize the diverse opportunities that await them.”
During their talks and panel discussions, speakers shared their insight into topics such as access to STEAM education, overcoming challenges and socioeconomic barriers, and strategies for fostering inclusion in STEAM fields. Students also had the opportunity to network with industry leaders and professionals, building connections to foster future collaborations.
Attendees also participated in hands-on scientific demonstrations, interaction with robots, and tours of MIT labs, providing a view of cutting-edge scientific research. The event also included musical performances from Latin American students from Berklee College of Music.
“I was thrilled to see the enthusiasm of young people and their parents and to be inspired by the great life stories of accomplished scientists and individuals from other fields making a positive impact in the real world,” says Edwin Pedrozo Peñafiel, assistant professor of physics at the University of Florida and an organizer. “This is why I strongly believe that representation matters.”
Welcoming a Nobel laureate
The first day of the forum opened with the welcoming words from Nergis Mavalvala, dean of the School of Science, and Boleslaw Wyslouch, director of the Laboratory for Nuclear Science and the MIT Bates Research and Engineering Center, and concluded with a keynote address by human rights activist Rigoberta Menchú Tum, 1992 Nobel Peace laureate and founder of the Rigoberta Menchú Tum Foundation. Reflecting upon Indigenous perspectives on science, she emphasized the importance of maintaining a humanistic perspective in scientific discovery. “My struggle has been one of constructing a humanistic perspective … that science, technology … are products of the strength of human beings,” Menchú remarked. She also shared her extraordinary story, encouraging students to persevere no matter the obstacles.
Diana Grass, a PhD Student in the Harvard-MIT Health Sciences and Technology program and organizer, shares, “As a woman in science and a first-generation student, I’ve experienced firsthand the impact of breaking barriers and the importance of representation. At Bridging Talents and Opportunities (BTO), we are shaping a future where opportunities are available to all. Seeing students from disadvantaged backgrounds, along with their parents, engage with some of today’s most influential scientists and leaders — who shared their own stories of resilience — was both inspiring and transformative. It ignited crucial conversations about how interdisciplinary collaboration in STEAM, grounded in humanity, is essential for tackling the critical challenges of our era.”
Power of the Arts
The second day concluded with a panel on “The Power of the Arts,” featuring actor, singer, and songwriter Carlos Ponce, as well as musician and producer Emilio Estefan. They were joined by journalist and author Luz María Doria, who moderated the discussion. Throughout the panel, the speakers recounted their inspiring journeys toward success in the entertainment industry. “This forum reaffirmed our commitment to bridging talent with opportunity,” says Ponce. “The energy and engagement from students, families, and speakers were incredible, fostering a space of learning, empowerment, and possibility.”
During the forum, a two-hour workshop was held that brought together scientists, nonprofit foundations, and business leaders to discuss concrete proposals for creating opportunities for young talents. In this workshop, they had the opportunity to share their ideas with one another. Key ideas and final takeaways from the workshop included developing strategic programs to match talented young students with mentors from diverse backgrounds who can serve as role models, better utilization of existing programs supporting underserved populations, dissemination of information about such programs, ideas to improve financial support for students pursuing education, and fostering extended collaborations between the three groups involved in the workshop.
Maria Angélica Cuellar, CEO of Incontact Group and a BTO organizer, says, “The event was absolutely spectacular and exceeded our expectations. We not only brought together leaders making a global impact in STEAM and business, but also secured financial commitments to support young talents. Through media coverage and streaming, our message reached every corner of the world, especially Latin America and the U.S. I’m deeply grateful for the commitment of each speaker and for the path now open to turn this dream of connecting stakeholders into tangible results and actions. An exciting challenge lies ahead, driving us to work even harder to create opportunities for these talented young people.”
“Bridging Talents and Opportunities was a unique event that brought together students, parents, professors, and leaders in different fields in a relatable and inspiring environment,” says Sebastián Ruiz Lopera, a PhD candidate in the Department of Electrical Engineering and Computer Science and an organizer. “Every speaker, panelist, and participant shared a story of resilience and passion that will motivate the next generation of young talents from disadvantaged backgrounds to become the new leaders and stakeholders.”
The 2024 BTO forum was made possible with the support of the Latinx Graduate Student Association at MIT, Laboratory of Nuclear Science, MIT MLK Scholars Program, Institute Community and Equity Office, the School of Science, the U.S. Department of Energy, University of Florida, CHN, JGMA Architects, Berklee College of Music, and the Harvard Colombian Student Society.
Killing the messengerA newly characterized anti-viral defense system in bacteria aborts infection through a novel mechanism by chemically altering mRNA.Like humans and other complex multicellular organisms, single-celled bacteria can fall ill and fight off viral infections. A bacterial virus is caused by a bacteriophage, or, more simply, phage, which is one of the most ubiquitous life forms on earth. Phages and bacteria are engaged in a constant battle, the virus attempting to circumvent the bacteria’s defenses, and the bacteria racing to find new ways to protect itself.
These anti-phage defense systems are carefully controlled, and prudently managed — dormant, but always poised to strike.
New open-access research recently published in Nature from the Laub Lab in the Department of Biology at MIT has characterized an anti-phage defense system in bacteria, CmdTAC. CmdTAC prevents viral infection by altering the single-stranded genetic code used to produce proteins, messenger RNA.
This defense system detects phage infection at a stage when the viral phage has already commandeered the host’s machinery for its own purposes. In the face of annihilation, the ill-fated bacterium activates a defense system that will halt translation, preventing the creation of new proteins and aborting the infection — but dooming itself in the process.
“When bacteria are in a group, they’re kind of like a multicellular organism that is not connected to one another. It’s an evolutionarily beneficial strategy for one cell to kill itself to save another identical cell,” says Christopher Vassallo, a postdoc and co-author of the study. “You could say it’s like self-sacrifice: One cell dies to protect the other cells.”
The enzyme responsible for altering the mRNA is called an ADP-ribosyltransferase. Researchers have characterized hundreds of these enzymes — although a few are known to target DNA or RNA, all but a handful target proteins. This is the first time these enzymes have been characterized targeting mRNA within cells.
Expanding understanding of anti-phage defense
Co-first author and graduate student Christopher Doering notes that it is only within the last decade or so that researchers have begun to appreciate the breadth of diversity and complexity of anti-phage defense systems. For example, CRISPR gene editing, a technique used in everything from medicine to agriculture, is rooted in research on the bacterial CRISPR-Cas9 anti-phage defense system.
CmdTAC is a subset of a widespread anti-phage defense mechanism called a toxin-antitoxin system. A TA system is just that: a toxin capable of killing or altering the cell’s processes rendered inert by an associated antitoxin.
Although these TA systems can be identified — if the toxin is expressed by itself, it kills or inhibits the growth of the cell; if the toxin and antitoxin are expressed together, the toxin is neutralized — characterizing the cascade of circumstances that activates these systems requires extensive effort. In recent years, however, many TA systems have been shown to serve as anti-phage defense.
Two general questions need to be answered to understand a viral defense system: How do bacteria detect an infection, and how do they respond?
Detecting infection
CmdTAC is a TA system with an additional element, and the three components generally exist in a stable complex: the toxic CmdT, the antitoxin CmdA, and an additional component called a chaperone, CmdC.
If the phage’s protective capsid protein is present, CmdC disassociates from CmdT and CmdA and interacts with the phage capsid protein instead. In the model outlined in the paper, the chaperone CmdC is, therefore, the sensor of the system, responsible for recognizing when an infection is occurring. Structural proteins, such as the capsid that protects the phage genome, are a common trigger because they’re abundant and essential to the phage.
The uncoupling of CmdC exposes the neutralizing antitoxin CmdA to be degraded, which releases the toxin CmdT to do its lethal work.
Toxicity on the loose
The researchers were guided by computational tools, so they knew that CmdT was likely an ADP-ribosyltransferase due to its similarities to other such enzymes. As the name suggests, the enzyme transfers an ADP ribose onto its target.
To determine if CmdT interacted with any sequences or positions in particular, they tested a mix of short sequences of single-stranded RNA. RNA has four bases: A, U, G, and C, and the evidence points to the enzyme recognizing GA sequences.
The CmdT modification of GA sequences in mRNA blocks their translation. The cessation of creating new proteins aborts the infection, preventing the phage from spreading beyond the host to infect other bacteria.
“Not only is it a new type of bacterial immune system, but the enzyme involved does something that’s never been seen before: the ADP-ribsolyation of mRNA,” Vassallo says.
Although the paper outlines the broad strokes of the anti-phage defense system, it’s unclear how CmdC interacts with the capsid protein, and how the chemical modification of GA sequences prevents translation.
Beyond bacteria
More broadly, exploring anti-phage defense aligns with the Laub Lab’s overall goal of understanding how bacteria function and evolve, but these results may have broader implications beyond bacteria.
Senior author Michael Laub, Salvador E. Luria Professor and Howard Hughes Medical Institute Investigator, says the ADP-ribosyltransferase has homologs in eukaryotes, including human cells. They are not well studied, and not among the Laub Lab’s research topics, but they are known to be up-regulated in response to viral infection.
“There are so many different — and cool — mechanisms by which organisms defend themselves against viral infection,” Laub says. “The notion that there may be some commonality between how bacteria defend themselves and how humans defend themselves is a tantalizing possibility.”
Smart handling of neutrons is crucial to fusion power successAssistant Professor Ethan Peterson is addressing some of the practical, overlooked issues that need to be worked out for viable fusion power plants.In fall 2009, when Ethan Peterson ’13 arrived at MIT as an undergraduate, he already had some ideas about possible career options. He’d always liked building things, even as a child, so he imagined his future work would involve engineering of some sort. He also liked physics. And he’d recently become intent on reducing our dependence on fossil fuels and simultaneously curbing greenhouse gas emissions, which made him consider studying solar and wind energy, among other renewable sources.
Things crystallized for him in the spring semester of 2010, when he took an introductory course on nuclear fusion, taught by Anne White, during which he discovered that when a deuterium nucleus and a tritium nucleus combine to produce a helium nucleus, an energetic (14 mega electron volt) neutron — traveling at one-sixth the speed of light — is released. Moreover, 1020 (100 billion billion) of these neutrons would be produced every second that a 500-megawatt fusion power plant operates. “It was eye-opening for me to learn just how energy-dense the fusion process is,” says Peterson, who became the Class of 1956 Career Development Professor of nuclear science and engineering in July 2024. “I was struck by the richness and interdisciplinary nature of the fusion field. This was an engineering discipline where I could apply physics to solve a real-world problem in a way that was both interesting and beautiful.”
He soon became a physics and nuclear engineering double major, and by the time he graduated from MIT in 2013, the U.S. Department of Energy (DoE) had already decided to cut funding for MIT’s Alcator C-Mod fusion project. In view of that facility’s impending closure, Peterson opted to pursue graduate studies at the University of Wisconsin. There, he acquired a basic science background in plasma physics, which is central not only to nuclear fusion but also to astrophysical phenomena such as the solar wind.
When Peterson received his PhD from Wisconsin in 2019, nuclear fusion had rebounded at MIT with the launch, a year earlier, of the SPARC project — a collaborative effort being carried out with the newly founded MIT spinout Commonwealth Fusion Systems. He returned to his alma mater as a postdoc and then a research scientist in the Plasma Science and Fusion Center, taking his time, at first, to figure out how to best make his mark in the field.
Minding your neutrons
Around that time, Peterson was participating in a community planning process, sponsored by the DoE, that focused on critical gaps that needed to be closed for a successful fusion program. In the course of these discussions, he came to realize that inadequate attention had been paid to the handling of neutrons, which carry 80 percent of the energy coming out of a fusion reaction — energy that needs to be harnessed for electrical generation. However, these neutrons are so energetic that they can penetrate through many tens of centimeters of material, potentially undermining the structural integrity of components and damaging vital equipment such as superconducting magnets. Shielding is also essential for protecting humans from harmful radiation.
One goal, Peterson says, is to minimize the number of neutrons that escape and, in so doing, to reduce the amount of lost energy. A complementary objective, he adds, “is to get neutrons to deposit heat where you want them to and to stop them from depositing heat where you don’t want them to.” These considerations, in turn, can have a profound influence on fusion reactor design. This branch of nuclear engineering, called neutronics — which analyzes where neutrons are created and where they end up going — has become Peterson’s specialty.
It was never a high-profile area of research in the fusion community — as plasma physics, for example, has always garnered more of the spotlight and more of the funding. That’s exactly why Peterson has stepped up. “The impacts of neutrons on fusion reactor design haven’t been a high priority for a long time,” he says. “I felt that some initiative needed to be taken,” and that prompted him to make the switch from plasma physics to neutronics. It has been his principal focus ever since — as a postdoc, a research scientist, and now as a faculty member.
A code to design by
The best way to get a neutron to transfer its energy is to make it collide with a light atom. Lithium, with an atomic number of three, or lithium-containing materials are normally good choices — and necessary for producing tritium fuel. The placement of lithium “blankets,” which are intended to absorb energy from neutrons and produce tritium, “is a critical part of the design of fusion reactors,” Peterson says. High-density materials, such as lead and tungsten, can be used, conversely, to block the passage of neutrons and other types of radiation. “You might want to layer these high- and low-density materials in a complicated way that isn’t immediately intuitive” he adds. Determining which materials to put where — and of what thickness and mass — amounts to a tricky optimization problem, which will affect the size, cost, and efficiency of a fusion power plant.
To that end, Peterson has developed modelling tools that can make analyses of these sorts easier and faster, thereby facilitating the design process. “This has traditionally been the step that takes the longest time and causes the biggest holdups,” he says. The models and algorithms that he and his colleagues are devising are general enough, moreover, to be compatible with a diverse range of fusion power plant concepts, including those that use magnets or lasers to confine the plasma.
Now that he’s become a professor, Peterson is in a position to introduce more people to nuclear engineering, and to neutronics in particular. “I love teaching and mentoring students, sharing the things I’m excited about,” he says. “I was inspired by all the professors I had in physics and nuclear engineering at MIT, and I hope to give back to the community in the same way.”
He also believes that if you are going to work on fusion, there is no better place to be than MIT, “where the facilities are second-to-none. People here are extremely innovative and passionate. And the sheer number of people who excel in their fields is staggering.” Great ideas can sometimes be sparked by off-the-cuff conversations in the hallway — something that happens more frequently than you expect, Peterson remarks. “All of these things taken together makes MIT a very special place.”
2024 Math Prize for Girls at MIT sees six-way tieContest hosted by the Department of Mathematics attracts 274 participants and celebrates 16th anniversary.After 274 young women spent two-and-a-half hours working through 20 advanced math problems for the 16th annual Advantage Testing Foundation/Jane Street Math Prize for Girls (MP4G) contest held Oct. 4-6 at MIT, a six-way tie was announced.
Hosted by the MIT Department of Mathematics and sponsored by the Advantage Testing Foundation and global trading firm Jane Street, MP4G is the largest math prize for girls in the world. The competitors, who came from across the United States and Canada, had scored high enough on the American Mathematics Competition exam to apply for and be accepted by MP4G. This year, MP4G received 891 applications to solve multistage problems in geometry, algebra, and trigonometry. This year's problems are listed on the MP4G website.
Because of the six-way tie, the $50,000 first-place prize and subsequent awards ($20,000 for second, $10,000 for third, $4,000 apiece for fourth and fifth and $2,000 for sixth place) was instead evenly divided, with each winner receiving $15,000. While each scored 15 out of 20, the winners were actually placed in order of how they answered the most difficult problems.
In first place was Shruti Arun, 11th grade, Cherry Creek High School, Colorado, who last year placed fourth; followed by Angela Liu, 12th grade, home-schooled, California; Sophia Hou, 11th grade, Thomas Jefferson High School for Science and Technology, Virginia; Susie Lu, 11th grade, Stanford Online High School, Washington, who last year placed 19th; Katie He, 12th grade, the Frazer School, Florida; and Katherine Liu, 12th grade, Clements High School, Texas — with the latter two having tied for seventh place last year.
The next round of winners, all with a score of 14, took home $1,000 each: Angela Ho, 11th grade, Stevenson High School, Illinois; Hannah Fox, 12th grade, Proof School, California; Selena Ge, 9th grade, Lexington High School, Massachusetts; Alansha Jiang, 12th grade, Newport High School, Washington; Laura Wang, 9th grade, Lakeside School, Washington; Alyssa Chu, 12th grade, Rye Country Day School, New York; Emily Yu, 12th grade, Mendon High School, New York; and Ivy Guo, 12th grade, Blair High School, Maryland.
The $2,000 Youth Prize to the highest-scoring contestant in 9th grade or below was shared evenly by Selena Ge and Laura Wang. In total, the event awards $100,000 in monetary prize to the top 14 contestants (including tie scores). Honorable mention trophies were awarded to the next 25 winners.
“I knew there were a lot of really smart people there, so the chances of me getting first wasn’t particularly high,” Katie He told a Florida newspaper. “When I heard six ways, I was so excited though,” He says, “because that’s just really cool that we all get to be happy about our performances and celebrate together and share the same joy.”
The event featured a keynote lecture by Harvard University professor of mathematics Lauren Williams on the "Combinatorics of Hopping Particles;” talks by Po-Shen Loh, professor of math at Carnegie Mellon University, and Maria Klawe, president of Math for America; and a musical performance by the MIT Logarhythms. Last year’s winner, Jessica Wan, volunteered as a proctor. Now a first-year at MIT, Wan won MP4G in 2022 and 2019. Alumna and doctoral candidate Nitya Mani was on hand to note, during her speech at the awards ceremony, how much bigger the event has grown over the years.
The day before the competition, attendees gathered to attend campus tours, icebreaker events, and networking sessions around MIT, at the Boston Marriott Cambridge, and at Kresge Auditorium, where the awards ceremony took place. Contestants also met MP4G alumnae at the Women in STEM Ask Me Anything event.
Math Community and Outreach Officer Michael King described the event as a “virtuous circle” where alumni return to encourage participants and help to keep the event running. “It’s good for MIT, because it attracts top female students from around the country. The atmosphere, with hundreds of girls excited about math and supported by their families, was wonderful. I thought to myself, ‘This is possible, to have rooms of math people that aren’t 80 percent men.’ The more women in math, the more role models. This is what inspires people to enter a discipline. MP4G creates a community of role models.”
Chris Peterson SM ’13, director of communications and special projects at MIT Admissions and Student Financial Services, agrees. “Everyone sees and appreciates the competitive function that Math Prize performs to identify and celebrate these highly talented young mathematicians. What’s less visible, but equally or even more important, is the crucial community role it plays as an affinity community to build relationships and a sense of belonging among these young women that will follow and empower them through the rest of their education and careers.”
Petersen also discussed life at MIT and the admissions process at the Art of Problem Solving’s recent free MIT Math Jam, as he has annually for the past decade. He was joined by MIT Math doctoral candidate Evan Chen ’18, a former deputy leader of the USA International Math Olympiad team.
Many alumnae returned to MIT to participate in a panel for attendees and their parents. For one panelist, MP4G is a family affair. Sheela Devadas, MP4G ’10 and ’11, is the sister of electrical engineering and computer science doctoral candidate and fellow MP4G alum Lalita; their mother, Sulochana, is MP4G’s program administrator.
“One of the goals of MP4G is to inspire young mathematicians,” says Devadas. “Although it is a competition, there is a lot of camaraderie between the contestants as well, and opportunities to meet both current undergraduate STEM majors and older role models who have pursued math-based careers. This aligned with my experience at MIT as a math major, where the atmosphere felt both competitive and collaborative in a way that inspired us.”
“There are many structural barriers and interpersonal issues facing women in STEM-oriented careers,” she adds. “One issue that is sometimes overlooked, which I have sometimes run into, is that both in school and in the workplace, it can be challenging to get your peers to respect your mathematical skill rather than pressuring you to take on tasks like note-taking or scheduling that are seen as more 'female' (though those tasks are also valuable and necessary).”
Another panelist, Jennifer Xiong ’23, talked about her time at MP4G, MIT, and her current role as a pharmaceutical researcher at Moderna.
“MP4G is what made me want to attend MIT, where I met my first MIT friend,” she says. Later, as an MIT student, she volunteered with MP4G to help her stay connected with the program. “MP4G is exciting because it brings together young girls who are interested in solving hard problems, to MIT campus, where they can build community and foster their interests in math.”
Volunteer Ranu Boppana ’87, the wife of MP4G founding director and MIT Math Research Affiliate Ravi Boppana PhD ’86, appreciates watching how this program has helped inspire women to pursue STEM education. “I’m most struck by the fact that MIT is now gender-balanced for undergraduates, but also impressed with what a more diverse place it is in every way.”
The Boppanas were inspired to found MP4G because their daughter was a mathlete in middle school and high school, and often the only girl in many regional competitions. “Ravi realized that the girls needed a community of their own, and role models to help them visualize seeing themselves in STEM.”
“Each year, the best part of MP4G is seeing the girls create wonderful networks for themselves, as some are often the only girls they know interested in math at home. This event is also such a fabulous introduction to MIT for them. I think this event helps MIT recruit the most mathematically talented girls in the country.”
Ravi also recently created the YouTube channel Boppana Math, geared toward high school students. “My goal is to create videos that are accessible to bright high school students, such as the participants in the Math Prize for Girls,” says Ravi. “My most recent video, 'Hypergraphs and Acute Triangles,' won an Honorable Mention at this year’s Summer of Math Exposition.”
The full list of winners is posted on the Art of Problem Solving website. The top 45 students are invited to take the 2024 Math Prize for Girls Olympiad at their schools. Canada/USA Mathcamp also provides $500 merit scholarships to the top 35 MP4G students who enroll in its summer program. This reflects a $250 increase to the scholarships. Applications to compete in next year’s MP4G will open in March 2025.
Quantum simulator could help uncover materials for high-performance electronicsBy emulating a magnetic field on a superconducting quantum computer, researchers can probe complex properties of materials.Quantum computers hold the promise to emulate complex materials, helping researchers better understand the physical properties that arise from interacting atoms and electrons. This may one day lead to the discovery or design of better semiconductors, insulators, or superconductors that could be used to make ever faster, more powerful, and more energy-efficient electronics.
But some phenomena that occur in materials can be challenging to mimic using quantum computers, leaving gaps in the problems that scientists have explored with quantum hardware.
To fill one of these gaps, MIT researchers developed a technique to generate synthetic electromagnetic fields on superconducting quantum processors. The team demonstrated the technique on a processor comprising 16 qubits.
By dynamically controlling how the 16 qubits in their processor are coupled to one another, the researchers were able to emulate how electrons move between atoms in the presence of an electromagnetic field. Moreover, the synthetic electromagnetic field is broadly adjustable, enabling scientists to explore a range of material properties.
Emulating electromagnetic fields is crucial to fully explore the properties of materials. In the future, this technique could shed light on key features of electronic systems, such as conductivity, polarization, and magnetization.
“Quantum computers are powerful tools for studying the physics of materials and other quantum mechanical systems. Our work enables us to simulate much more of the rich physics that has captivated materials scientists,” says Ilan Rosen, an MIT postdoc and lead author of a paper on the quantum simulator.
The senior author is William D. Oliver, the Henry Ellis Warren professor of electrical engineering and computer science and of physics, director of the Center for Quantum Engineering, leader of the Engineering Quantum Systems group, and associate director of the Research Laboratory of Electronics. Oliver and Rosen are joined by others in the departments of Electrical Engineering and Computer Science and of Physics and at MIT Lincoln Laboratory. The research appears today in Nature Physics.
A quantum emulator
Companies like IBM and Google are striving to build large-scale digital quantum computers that hold the promise of outperforming their classical counterparts by running certain algorithms far more rapidly.
But that’s not all quantum computers can do. The dynamics of qubits and their couplings can also be carefully constructed to mimic the behavior of electrons as they move among atoms in solids.
“That leads to an obvious application, which is to use these superconducting quantum computers as emulators of materials,” says Jeffrey Grover, a research scientist at MIT and co-author on the paper.
Rather than trying to build large-scale digital quantum computers to solve extremely complex problems, researchers can use the qubits in smaller-scale quantum computers as analog devices to replicate a material system in a controlled environment.
“General-purpose digital quantum simulators hold tremendous promise, but they are still a long way off. Analog emulation is another approach that may yield useful results in the near-term, particularly for studying materials. It is a straightforward and powerful application of quantum hardware,” explains Rosen. “Using an analog quantum emulator, I can intentionally set a starting point and then watch what unfolds as a function of time.”
Despite their close similarity to materials, there are a few important ingredients in materials that can’t be easily reflected on quantum computing hardware. One such ingredient is a magnetic field.
In materials, electrons “live” in atomic orbitals. When two atoms are close to one another, their orbitals overlap and electrons can “hop” from one atom to another. In the presence of a magnetic field, that hopping behavior becomes more complex.
On a superconducting quantum computer, microwave photons hopping between qubits are used to mimic electrons hopping between atoms. But, because photons are not charged particles like electrons, the photons’ hopping behavior would remain the same in a physical magnetic field.
Since they can’t just turn on a magnetic field in their simulator, the MIT team employed a few tricks to synthesize the effects of one instead.
Tuning up the processor
The researchers adjusted how adjacent qubits in the processor were coupled to each other to create the same complex hopping behavior that electromagnetic fields cause in electrons.
To do that, they slightly changed the energy of each qubit by applying different microwave signals. Usually, researchers will set qubits to the same energy so that photons can hop from one to another. But for this technique, they dynamically varied the energy of each qubit to change how they communicate with each other.
By precisely modulating these energy levels, the researchers enabled photons to hop between qubits in the same complex manner that electrons hop between atoms in a magnetic field.
Plus, because they can finely tune the microwave signals, they can emulate a range of electromagnetic fields with different strengths and distributions.
The researchers undertook several rounds of experiments to determine what energy to set for each qubit, how strongly to modulate them, and the microwave frequency to use.
“The most challenging part was finding modulation settings for each qubit so that all 16 qubits work at once,” Rosen says.
Once they arrived at the right settings, they confirmed that the dynamics of the photons uphold several equations that form the foundation of electromagnetism. They also demonstrated the “Hall effect,” a conduction phenomenon that exists in the presence of an electromagnetic field.
These results show that their synthetic electromagnetic field behaves like the real thing.
Moving forward, they could use this technique to precisely study complex phenomena in condensed matter physics, such as phase transitions that occur when a material changes from a conductor to an insulator.
“A nice feature of our emulator is that we need only change the modulation amplitude or frequency to mimic a different material system. In this way, we can scan over many materials properties or model parameters without having to physically fabricate a new device each time.” says Oliver.
While this work was an initial demonstration of a synthetic electromagnetic field, it opens the door to many potential discoveries, Rosen says.
“The beauty of quantum computers is that we can look at exactly what is happening at every moment in time on every qubit, so we have all this information at our disposal. We are in a very exciting place for the future,” he adds.
This work is supported, in part, by the U.S. Department of Energy, the U.S. Defense Advanced Research Projects Agency (DARPA), the U.S. Army Research Office, the Oak Ridge Institute for Science and Education, the Office of the Director of National Intelligence, NASA, and the National Science Foundation.
AXIS mission selected as NASA Astrophysics Probe competition finalistMIT Kavli Institute scientists and collaborators will produce a concept study to launch a $1B experiment to investigate the X-ray universe.The MIT Kavli Institute for Astrophysics and Space Research (MKI) is a project lead for one of two finalist missions recently selected for NASA's new Probe Explorers program. Working with collaborators at the University of Maryland and Goddard Space Flight Research Center, the team will produce a one-year concept study to launch the Advanced X-ray Imaging Satellite (AXIS) in 2032.
Erin Kara, associate professor of physics and astrophysicist at MIT, is the deputy principal investigator for AXIS. The MIT team includes MKI scientists Eric Miller, Mark Bautz, Catherine Grant, Michael McDonald, and Kevin Burdge. Says Kara, "I am honored to be working with this amazing team in ushering in a new era for X-ray astronomy."
The AXIS mission is designed to revolutionize the view scientists have of high-energy events and environments in the universe using new technologies capable of seeing even deeper into space and further back in time.
"If selected to move forward," explains Kara, "AXIS will answer some of the biggest mysteries in modern astrophysics, from the formation of supermassive black holes to the progenitors of the most energetic and explosive events in the universe to the effects of stars on exoplanets. Simply put, it's the next-generation observatory we need to transform our understanding of the universe."
Critical to AXIS's success is the CCD focal plane — an array of imaging devices that record the properties of the light coming into the telescope. If selected, MKI scientists will work with colleagues at MIT Lincoln Laboratory and Stanford University to develop this high-speed camera, which sits at the heart of the telescope, connected to the X-ray Mirror Assembly and telescope tube. The work to create the array builds on previous imaging technology developed by MKI and Lincoln Laboratory, including instruments flying on the Chandra X-ray Observatory, the Suzaku X-ray Observatory, and the Transiting Exoplanet Survey Satellite (TESS).
Camera lead Eric Miller notes that "the advanced detectors that we will use provide the same excellent sensitivity as previous instruments, but operating up to 100 times faster to keep up with all of the X-rays focused by the mirror." As such, the development of the CCD focal plane will have significant impact in both scientific and technological realms.
"Engineering the array over the next year," adds Kara, "will lay the groundwork not just for AXIS, but for future missions as well."
MIT Schwarzman College of Computing launches postdoctoral program to advance AI across disciplinesThe new Tayebati Postdoctoral Fellowship Program will support leading postdocs to bring cutting-edge AI to bear on research in scientific discovery or music.The MIT Stephen A. Schwarzman College of Computing has announced the launch of a new program to support postdocs conducting research at the intersection of artificial intelligence and particular disciplines.
The Tayebati Postdoctoral Fellowship Program will focus on AI for addressing the most challenging problems in select scientific research areas, and on AI for music composition and performance. The program will welcome an inaugural cohort of up to six postdocs for a one-year term, with the possibility of renewal for a second term.
Supported by a $20 million gift from Parviz Tayebati, an entrepreneur and executive with a broad technical background and experience with startup companies, the program will empower top postdocs by providing an environment that facilitates their academic and professional development and enables them to pursue ambitious discoveries. “I am proud to support a fellowship program that champions interdisciplinary research and fosters collaboration across departments. My hope is that this gift will inspire a new generation of scholars whose research advances knowledge and nurtures innovation that transcends traditional boundaries,” says Tayebati.
"Artificial intelligence holds tremendous potential to accelerate breakthroughs in science and ignite human creativity," says Dan Huttenlocher, dean of the Schwarzman College of Computing and Henry Ellis Warren Professor of Electrical Engineering and Computer Science. “This new postdoc program is a remarkable opportunity to cultivate exceptional bilingual talent combining AI and another discipline. The program will offer fellows the chance to engage in research at the forefront of both AI and another field, collaborating with leading experts across disciplines. We are deeply thankful to Parviz for his foresight in supporting the development of researchers in this increasingly important area.”
Candidates accepted into the program will work on projects that encompass one of six disciplinary areas: biology/bioengineering, brain and cognitive sciences, chemistry/chemical engineering, materials science and engineering, music, and physics. Each fellow will have a faculty mentor in the disciplinary area as well as in AI.
The Tayebati Postdoctoral Fellowship Program is a key component of a larger focus of the MIT Schwarzman College of Computing aimed at fostering innovative research in computing. As part of this focus, the college has three postdoctoral programs, each of which provides training and mentorship to fellows, broadens their research horizons, and helps them develop expertise in computing, including its intersection with other disciplines.
Other programs include MEnTorEd Opportunities in Research (METEOR), which was established by the Computer Science and Artificial Intelligence Laboratory in 2020. Recently expanded to span MIT through the college, the goal of METEOR is to support exceptional scholars in computer science and AI and to broaden participation in the field.
In addition, the Social and Ethical Responsibilities of Computing (SERC), a cross-cutting initiative of the MIT Schwarzman College of Computing, offers researchers exploring how computing is reshaping society the opportunity to participate as a SERC postdoc. SERC postdocs engage in a number of activities throughout the year, including leading interdisciplinary teams of MIT undergraduate and graduate students, known as SERC Scholars, to work on research projects investigating such topics as generative AI and democracy, combating deepfakes, examining data ownership, and the societal impact of gamification, among others.
MIT affiliates receive 2024-25 awards and honors from the American Physical SocietyTwo faculty, a graduate student, and 10 additional alumni receive top awards and prizes; four faculty, one senior researcher, and seven alumni named APS Fellows.A number of individuals with MIT ties have received honors from the American Physical Society (APS) for 2024 and 2025.
Awardees include Professor Frances Ross; Professor Vladan Vuletić, graduate student Jiliang Hu ’19, PhD ’24; as well as 10 alumni. New APS Fellows include Professor Joseph Checkelsky, Senior Researcher John Chiaverini, Associate Professor Areg Danagoulian, Professor Ruben Juanes, and seven alumni.
Frances M. Ross, the TDK Professor in Materials Science and Engineering, received the 2025 Joseph F. Keithley Award For Advances in Measurement Science “for groundbreaking advances in in situ electron microscopy in vacuum and liquid environments.”
Ross uses transmission electron microscopy to watch crystals as they grow and react under different conditions, including both liquid and gaseous environments. The microscopy techniques developed over Ross’ research career help in exploring growth mechanisms during epitaxy, catalysis, and electrochemical deposition, with applications in microelectronics and energy storage. Ross’ research group continues to develop new microscopy instrumentation to enable deeper exploration of these processes.
Vladan Vuletić, the Lester Wolfe Professor of Physics, received the 2025 Arthur L. Schawlow Prize in Laser Science “for pioneering work on spin squeezing for optical atomic clocks, quantum nonlinear optics, and laser cooling to quantum degeneracy.” Vuletić’s research includes ultracold atoms, laser cooling, large-scale quantum entanglement, quantum optics, precision tests of physics beyond the Standard Model, and quantum simulation and computing with trapped neutral atoms.
His Experimental Atomic Physics Group is also affiliated with the MIT-Harvard Center for Ultracold Atoms and the Research Laboratory of Electronics (RLE). In 2020, his group showed that the precision of current atomic clocks could be improved by entangling the atoms — a quantum phenomenon by which particles are coerced to behave in a collective, highly correlated state.
Jiliang Hu received the 2024 Award for Outstanding Doctoral Thesis Research in Biological Physics “for groundbreaking biophysical contributions to microbial ecology that bridge experiment and theory, showing how only a few coarse-grained features of ecological networks can predict emergent phases of diversity, dynamics, and invasibility in microbial communities.”
Hu is working in PhD advisor Professor Jeff Gore’s lab. He is interested in exploring the high-dimensional dynamics and emergent phenomena of complex microbial communities. In his first project, he demonstrated that multi-species communities can be described by a phase diagram as a function of the strength of interspecies interactions and the diversity of the species pool. He is now studying alternative stable states and the role of migration in the dynamics and biodiversity of metacommunities.
Alumni receiving awards:
Riccardo Betti PhD ’92 is the 2024 recipient of the John Dawson Award in Plasma Physics “for pioneering the development of statistical modeling to predict, design, and analyze implosion experiments on the 30kJ OMEGA laser, achieving hot spot energy gains above unity and record Lawson triple products for direct-drive laser fusion.”
Javier Mauricio Duarte ’10 received the 2024 Henry Primakoff Award for Early-Career Particle Physics “for accelerating trigger technologies in experimental particle physics with novel real-time approaches by embedding artificial intelligence and machine learning in programmable gate arrays, and for critical advances in Higgs physics studies at the Large Hadron Collider in all-hadronic final states.”
Richard Furnstahl ’18 is the 2025 recipient of the Feshbach Prize Theoretical Nuclear Physics “for foundational contributions to calculations of nuclei, including applying the Similarity Renormalization Group to the nuclear force, grounding nuclear density functional theory in those forces, and using Bayesian methods to quantify the uncertainties in effective field theory predictions of nuclear observables.”
Harold Yoonsung Hwang ’93, SM ’93 is the 2024 recipient of the James C. McGroddy Prize for New Materials “for pioneering work in oxide interfaces, dilute superconductivity in heterostructures, freestanding oxide membranes, and superconducting nickelates using pulsed laser deposition, as well as for significant early contributions to the physics of bulk transition metal oxides.”
James P. Knauer ’72 received the 2024 John Dawson Award in Plasma Physics “for pioneering the development of statistical modeling to predict, design, and analyze implosion experiments on the 30kJ OMEGA laser, achieving hot spot energy gains above unity and record Lawson triple products for direct-drive laser fusion.”
Sekazi Mtingwa ’71 is the 2025 recipient of the John Wheatley Award “for exceptional contributions to capacity building in Africa, the Middle East, and other developing regions, including leadership in training researchers in beamline techniques at synchrotron light sources and establishing the groundwork for future facilities in the Global South.
Michael Riordan ’68, PhD ’73 received the 2025 Abraham Pais Prize for History of Physics, which “recognizes outstanding scholarly achievements in the history of physics.”
Charles E. Sing PhD ’12 received the 2024 John H. Dillon Medal “for pioneering advances in polyelectrolyte phase behavior and polymer dynamics using theory and computational modeling.”
David W. Taylor ’01 received the 2025 Jonathan F. Reichert and Barbara Wolff-Reichert Award for Excellence in Advanced Laboratory Instruction “for continuous physical measurement laboratory improvements, leveraging industrial and academic partnerships that enable innovative and diversified independent student projects, and giving rise to practical skillsets yielding outstanding student outcomes.”
Wennie Wang ’13 is the 2025 recipient of the Maria Goeppert Mayer Award “for outstanding contributions to the field of materials science, including pioneering research on defective transition metal oxides for energy sustainability, a commitment to broadening participation of underrepresented groups in computational materials science, and leadership and advocacy in the scientific community.”
APS Fellows
Joseph Checkelsky, the Mitsui Career Development Associate Professor of Physics, received the 2024 Division of Condensed Matter Physics Fellowship “for pioneering contributions to the synthesis and study of quantum materials, including kagome and pyrochlore metals and natural superlattice compounds.”
Affiliated with the MIT Materials Research Laboratory and the MIT Center for Quantum Engineering, Checkelsky is working at the intersection of materials synthesis and quantum physics to discover new materials and physical phenomena to expand the boundaries of understanding of quantum mechanical condensed matter systems, as well as open doorways to new technologies by realizing emergent electronic and magnetic functionalities. Research in Checkelsky’s lab focuses on the study of exotic electronic states of matter through the synthesis, measurement, and control of solid-state materials. His research includes studying correlated behavior in topologically nontrivial materials, the role of geometrical phases in electronic systems, and novel types of geometric frustration.
John Chiaverini, a senior staff member in the Quantum Information and Integrated Nanosystems group and an MIT principal investigator in RLE, was elected a 2024 Fellow of the American Physical Society in the Division of Quantum Information “for pioneering contributions to experimental quantum information science, including early demonstrations of quantum algorithms, the development of the surface-electrode ion trap, and groundbreaking work in integrated photonics for trapped-ion quantum computation.”
Chiaverini is pursuing research in quantum computing and precision measurement using individual atoms. Currently, Chiaverini leads a team developing novel technologies for control of trapped-ion qubits, including trap-integrated optics and electronics; this research has the potential to allow scaling of trapped-ion systems to the larger numbers of ions needed for practical applications while maintaining high levels of control over their quantum states. He and the team are also exploring new techniques for the rapid generation of quantum entanglement between ions, as well as investigating novel encodings of quantum information that have the potential to yield higher-fidelity operations than currently available while also providing capabilities to correct the remaining errors.
Areg Danagoulian, associate professor of nuclear science and engineering, received the 2024 Forum on Physics and Society Fellowship “for seminal technological contributions in the field of arms control and cargo security, which significantly benefit international security.”
His current research interests focus on nuclear physics applications in societal problems, such as nuclear nonproliferation, technologies for arms control treaty verification, nuclear safeguards, and cargo security. Danagoulian also serves as the faculty co-director for MIT’s MISTI Eurasia program.
Ruben Juanes, professor of civil and environmental engineering and earth, atmospheric and planetary sciences (CEE/EAPS) received the 2024 Division of Fluid Dynamics Fellowship “for fundamental advances — using experiments, innovative imaging, and theory — in understanding the role of wettability for controlling the dynamics of fluid displacement in porous media and geophysical flows, and exploiting this understanding to optimize.”
An expert in the physics of multiphase flow in porous media, Juanes uses a mix of theory, computational, and real-life experiments to establish a fundamental understanding of how different fluids such as oil, water, and gas move through rocks, soil, or underwater reservoirs to solve energy and environmental-driven geophysical problems. His major contributions have been in developing improved safety and effectiveness of carbon sequestration, advanced understanding of fluid interactions in porous media for energy and environmental applications, imaging and computational techniques for real-time monitoring of subsurface fluid flows, and insights into how underground fluid movement contributes to landslides, floods, and earthquakes.
Alumni receiving fellowships:
Constantia Alexandrou PhD ’85 is the 2024 recipient of the Division of Nuclear Physics Fellowship “for the pioneering contributions in calculating nucleon structure observables using lattice QCD.”
Daniel Casey PhD ’12 received the 2024 Division of Plasma Physics Fellowship “for outstanding contributions to the understanding of the stagnation conditions required to achieve ignition.”
Maria K. Chan PhD ’09 is the 2024 recipient of the Topical Group on Energy Research and Applications Fellowship “for contributions to methodological innovations, developments, and demonstrations toward the integration of computational modeling and experimental characterization to improve the understanding and design of renewable energy materials.”
David Humphreys ’82, PhD ’91 received the 2024 Division of Plasma Physics Fellowship “for sustained leadership in developing the field of model-based dynamic control of magnetically confined plasmas, and for providing important and timely contributions to the understanding of tokamak stability, disruptions, and halo current physics.
Eric Torrence PhD ’97 received the 2024 Division of Particles and Fields Fellowship “for significant contributions with the ATLAS and FASER Collaborations, particularly in the searches for new physics, measurement of the LHC luminosity, and for leadership in the operations of both experiments.”
Tiffany S. Santos ’02, PhD ’07 is the 2024 recipient of the Topical Group on Magnetism and Its Applications Fellowship “for innovative contributions in synthesis and characterization of novel ultrathin magnetic films and interfaces, and tailoring their properties for optimal performance, especially in magnetic data storage and spin-transport devices.”
Lei Zhou ’14, PhD ’19 received the 2024 Forum on Industrial and Applied Physics Fellowship “for outstanding and sustained contributions to the fields of metamaterials, especially for proposing metasurfaces as a bridge to link propagating waves and surface waves.”
Scientists discover molecules that store much of the carbon in space The discovery of pyrene derivatives in a distant interstellar cloud may help to reveal how our own solar system formed.A team led by researchers at MIT has discovered that a distant interstellar cloud contains an abundance of pyrene, a type of large, carbon-containing molecule known as a polycyclic aromatic hydrocarbon (PAH).
The discovery of pyrene in this far-off cloud, which is similar to the collection of dust and gas that eventually became our own solar system, suggests that pyrene may have been the source of much of the carbon in our solar system. That hypothesis is also supported by a recent finding that samples returned from the near-Earth asteroid Ryugu contain large quantities of pyrene.
“One of the big questions in star and planet formation is: How much of the chemical inventory from that early molecular cloud is inherited and forms the base components of the solar system? What we’re looking at is the start and the end, and they’re showing the same thing. That’s pretty strong evidence that this material from the early molecular cloud finds its way into the ice, dust, and rocky bodies that make up our solar system,” says Brett McGuire, an assistant professor of chemistry at MIT.
Due to its symmetry, pyrene itself is invisible to the radio astronomy techniques that have been used to detect about 95 percent of molecules in space. Instead, the researchers detected an isomer of cyanopyrene, a version of pyrene that has reacted with cyanide to break its symmetry. The molecule was detected in a distant cloud known as TMC-1, using the 100-meter Green Bank Telescope (GBT), a radio telescope at the Green Bank Observatory in West Virginia.
McGuire and Ilsa Cooke, an assistant professor of chemistry at the University of British Colombia, are the senior authors of a paper describing the findings, which appears today in Science. Gabi Wenzel, an MIT postdoc in McGuire’s group, is the lead author of the study.
Carbon in space
PAHs, which contain rings of carbon atoms fused together, are believed to store 10 to 25 percent of the carbon that exists in space. More than 40 years ago, scientists using infrared telescopes began detecting features that are thought to belong to vibrational modes of PAHs in space, but this technique couldn’t reveal exactly which types of PAHs were out there.
“Since the PAH hypothesis was developed in the 1980s, many people have accepted that PAHs are in space, and they have been found in meteorites, comets, and asteroid samples, but we can’t really use infrared spectroscopy to unambiguously identify individual PAHs in space,” Wenzel says.
In 2018, a team led by McGuire reported the discovery of benzonitrile — a six-carbon ring attached to a nitrile (carbon-nitrogen) group — in TMC-1. To make this discovery, they used the GBT, which can detect molecules in space by their rotational spectra — distinctive patterns of light that molecules give off as they tumble through space. In 2021, his team detected the first individual PAHs in space: two isomers of cyanonaphthalene, which consists of two rings fused together, with a nitrile group attached to one ring.
On Earth, PAHs commonly occur as byproducts of burning fossil fuels, and they’re also found in char marks on grilled food. Their discovery in TMC-1, which is only about 10 kelvins, suggested that it may also be possible for them to form at very low temperatures.
The fact that PAHs have also been found in meteorites, asteroids, and comets has led many scientists to hypothesize that PAHs are the source of much of the carbon that formed our own solar system. In 2023, researchers in Japan found large quantities of pyrene in samples returned from the asteroid Ryugu during the Hayabusa2 mission, along with smaller PAHs including naphthalene.
That discovery motivated McGuire and his colleagues to look for pyrene in TMC-1. Pyrene, which contains four rings, is larger than any of the other PAHs that have been detected in space. In fact, it’s the third-largest molecule identified in space, and the largest ever detected using radio astronomy.
Before looking for these molecules in space, the researchers first had to synthesize cyanopyrene in the laboratory. The cyano or nitrile group is necessary for the molecule to emit a signal that a radio telescope can detect. The synthesis was performed by MIT postdoc Shuo Zhang in the group of Alison Wendlandt, an MIT associate professor of chemistry.
Then, the researchers analyzed the signals that the molecules emit in the laboratory, which are exactly the same as the signals that they emit in space.
Using the GBT, the researchers found these signatures throughout TMC-1. They also found that cyanopyrene accounts for about 0.1 percent of all the carbon found in the cloud, which sounds small but is significant when one considers the thousands of different types of carbon-containing molecules that exist in space, McGuire says.
“While 0.1 percent doesn’t sound like a large number, most carbon is trapped in carbon monoxide (CO), the second-most abundant molecule in the universe besides molecular hydrogen. If we set CO aside, one in every few hundred or so remaining carbon atoms is in pyrene. Imagine the thousands of different molecules that are out there, nearly all of them with many different carbon atoms in them, and one in a few hundred is in pyrene,” he says. “That is an absolutely massive abundance. An almost unbelievable sink of carbon. It’s an interstellar island of stability.”
Ewine van Dishoeck, a professor of molecular astrophysics at Leiden Observatory in the Netherlands, called the discovery “unexpected and exciting.”
“It builds on their earlier discoveries of smaller aromatic molecules, but to make the jump now to the pyrene family is huge. Not only does it demonstrate that a significant fraction of carbon is locked up in these molecules, but it also points to different formation routes of aromatics than have been considered so far,” says van Dishoeck, who was not involved in the research.
An abundance of pyrene
Interstellar clouds like TMC-1 may eventually give rise to stars, as clumps of dust and gas coalesce into larger bodies and begin to heat up. Planets, asteroids, and comets arise from some of the gas and dust that surround young stars. Scientists can’t look back in time at the interstellar cloud that gave rise to our own solar system, but the discovery of pyrene in TMC-1, along with the presence of large amounts of pyrene in the asteroid Ryugu, suggests that pyrene may have been the source of much of the carbon in our own solar system.
“We now have, I would venture to say, the strongest evidence ever of this direct molecular inheritance from the cold cloud all the way through to the actual rocks in the solar system,” McGuire says.
The researchers now plan to look for even larger PAH molecules in TMC-1. They also hope to investigate the question of whether the pyrene found in TMC-1 was formed within the cold cloud or whether it arrived from elsewhere in the universe, possibly from the high-energy combustion processes that surround dying stars.
The research was funded in part by a Beckman Foundation Young Investigator Award, the Schmidt Futures, the U.S. National Science Foundation, the Natural Sciences and Engineering Research Council of Canada, the Goddard Center for Astrobiology, and the NASA Planetary Science Division Internal Scientist Funding Program.
Physicists discover first “black hole triple”System observed 8,000 light-years away may be the first direct evidence of “gentle” black hole formation.Many black holes detected to date appear to be part of a pair. These binary systems comprise a black hole and a secondary object — such as a star, a much denser neutron star, or another black hole — that spiral around each other, drawn together by the black hole’s gravity to form a tight orbital pair.
Now a surprising discovery is expanding the picture of black holes, the objects they can host, and the way they form.
In a study appearing today in Nature, physicists at MIT and Caltech report that they have observed a “black hole triple” for the first time. The new system holds a central black hole in the act of consuming a small star that’s spiraling in very close to the black hole, every 6.5 days — a configuration similar to most binary systems. But surprisingly, a second star appears to also be circling the black hole, though at a much greater distance. The physicists estimate this far-off companion is orbiting the black hole every 70,000 years.
That the black hole seems to have a gravitational hold on an object so far away is raising questions about the origins of the black hole itself. Black holes are thought to form from the violent explosion of a dying star — a process known as a supernova, by which a star releases a huge amount of energy and light in a final burst before collapsing into an invisible black hole.
The team’s discovery, however, suggests that if the newly-observed black hole resulted from a typical supernova, the energy it would have released before it collapsed would have kicked away any loosely bound objects in its outskirts. The second, outer star, then, shouldn’t still be hanging around.
Instead, the team suspects the black hole formed through a more gentle process of “direct collapse,” in which a star simply caves in on itself, forming a black hole without a last dramatic flash. Such a gentle origin would hardly disturb any loosely bound, faraway objects.
Because the new triple system includes a very far-off star, this suggests the system’s black hole was born through a gentler, direct collapse. And while astronomers have observed more violent supernovae for centuries, the team says the new triple system could be the first evidence of a black hole that formed from this more gentle process.
“We think most black holes form from violent explosions of stars, but this discovery helps call that into question,” says study author Kevin Burdge, a Pappalardo Fellow in the MIT Department of Physics. “This system is super exciting for black hole evolution, and it also raises questions of whether there are more triples out there.”
The study’s co-authors at MIT are Erin Kara, Claude Canizares, Deepto Chakrabarty, Anna Frebel, Sarah Millholland, Saul Rappaport, Rob Simcoe, and Andrew Vanderburg, along with Kareem El-Badry at Caltech.
Tandem motion
The discovery of the black hole triple came about almost by chance. The physicists found it while looking through Aladin Lite, a repository of astronomical observations, aggregated from telescopes in space and all around the world. Astronomers can use the online tool to search for images of the same part of the sky, taken by different telescopes that are tuned to various wavelengths of energy and light.
The team had been looking within the Milky Way galaxy for signs of new black holes. Out of curiosity, Burdge reviewed an image of V404 Cygni — a black hole about 8,000 light years from Earth that was one of the very first objects ever to be confirmed as a black hole, in 1992. Since then, V404 Cygni has become one of the most well-studied black holes, and has been documented in over 1,300 scientific papers. However, none of those studies reported what Burdge and his colleagues observed.
As he looked at optical images of V404 Cygni, Burdge saw what appeared to be two blobs of light, surprisingly close to each other. The first blob was what others determined to be the black hole and an inner, closely orbiting star. The star is so close that it is shedding some of its material onto the black hole, and giving off the light that Burdge could see. The second blob of light, however, was something that scientists did not investigate closely, until now. That second light, Burdge determined, was most likely coming from a very far-off star.
“The fact that we can see two separate stars over this much distance actually means that the stars have to be really very far apart,” says Burdge, who calculated that the outer star is 3,500 astronomical units (AU) away from the black hole (1 AU is the distance between the Earth and sun). In other words, the outer star is 3,500 times father away from the black hole as the Earth is from the sun. This is also equal to 100 times the distance between Pluto and the sun.
The question that then came to mind was whether the outer star was linked to the black hole and its inner star. To answer this, the researchers looked to Gaia, a satellite that has precisely tracked the motions of all the stars in the galaxy since 2014. The team analyzed the motions of the inner and outer stars over the last 10 years of Gaia data and found that the stars moved exactly in tandem, compared to other neighboring stars. They calculated that the odds of this kind of tandem motion are about one in 10 million.
“It’s almost certainly not a coincidence or accident,” Burdge says. “We’re seeing two stars that are following each other because they’re attached by this weak string of gravity. So this has to be a triple system.”
Pulling strings
How, then, could the system have formed? If the black hole arose from a typical supernova, the violent explosion would have kicked away the outer star long ago.
“Imagine you’re pulling a kite, and instead of a strong string, you’re pulling with a spider web,” Burdge says. “If you tugged too hard, the web would break and you’d lose the kite. Gravity is like this barely bound string that’s really weak, and if you do anything dramatic to the inner binary, you’re going to lose the outer star.”
To really test this idea, however, Burdge carried out simulations to see how such a triple system could have evolved and retained the outer star.
At the start of each simulation, he introduced three stars (the third being the black hole, before it became a black hole). He then ran tens of thousands of simulations, each one with a slightly different scenario for how the third star could have become a black hole, and subsequently affected the motions of the other two stars. For instance, he simulated a supernova, varying the amount and direction of energy that it gave off. He also simulated scenarios of direct collapse, in which the third star simply caved in on itself to form a black hole, without giving off any energy.
“The vast majority of simulations show that the easiest way to make this triple work is through direct collapse,” Burdge says.
In addition to giving clues to the black hole’s origins, the outer star has also revealed the system’s age. The physicists observed that the outer star happens to be in the process of becoming a red giant — a phase that occurs at the end of a star’s life. Based on this stellar transition, the team determined that the outer star is about 4 billion years old. Given that neighboring stars are born around the same time, the team concludes that the black hole triple is also 4 billion years old.
“We’ve never been able to do this before for an old black hole,” Burdge says. “Now we know V404 Cygni is part of a triple, it could have formed from direct collapse, and it formed about 4 billion years ago, thanks to this discovery.”
This work was supported, in part, by the National Science Foundation.
Brain pathways that control dopamine release may influence motor controlThe newly identified pathways appear to relay emotional information that helps to shape the motivation to take action.Within the human brain, movement is influenced by a brain region called the striatum, which sends instructions to motor neurons in the brain. Those instructions are conveyed by two pathways, one that initiates movement (“go”) and one that suppresses it (“no-go”).
In a new study, MIT researchers have discovered an additional two pathways that arise in the striatum and appear to modulate the effects of the go and no-go pathways. These newly discovered pathways connect to dopamine-producing neurons in the brain — one stimulates dopamine release and the other inhibits it.
By controlling the amount of dopamine in the brain via clusters of neurons known as striosomes, these pathways appear to modify the instructions given by the go and no-go pathways. They may be especially involved in influencing decisions that have a strong emotional component, the researchers say.
“Among all the regions of the striatum, the striosomes alone turned out to be able to project to the dopamine-containing neurons, which we think has something to do with motivation, mood, and controlling movement,” says Ann Graybiel, an MIT Institute Professor, a member of MIT’s McGovern Institute for Brain Research, and the senior author of the new study.
Iakovos Lazaridis, a research scientist at the McGovern Institute, is the lead author of the paper, which appears today in the journal Current Biology.
New pathways
Graybiel has spent much of her career studying the striatum, a structure located deep within the brain that is involved in learning and decision-making, as well as control of movement.
Within the striatum, neurons are arranged in a labyrinth-like structure that includes striosomes, which Graybiel discovered in the 1970s. The classical go and no-go pathways arise from neurons that surround the striosomes, which are known collectively as the matrix. The matrix cells that give rise to these pathways receive input from sensory processing regions such as the visual cortex and auditory cortex. Then, they send go or no-go commands to neurons in the motor cortex.
However, the function of the striosomes, which are not part of those pathways, remained unknown. For many years, researchers in Graybiel’s lab have been trying to solve that mystery.
Their previous work revealed that striosomes receive much of their input from parts of the brain that process emotion. Within striosomes, there are two major types of neurons, classified as D1 and D2. In a 2015 study, Graybiel found that one of these cell types, D1, sends input to the substantia nigra, which is the brain’s major dopamine-producing center.
It took much longer to trace the output of the other set, D2 neurons. In the new Current Biology study, the researchers discovered that those neurons also eventually project to the substantia nigra, but first they connect to a set of neurons in the globus palladus, which inhibits dopamine output. This pathway, an indirect connection to the substantia nigra, reduces the brain’s dopamine output and inhibits movement.
The researchers also confirmed their earlier finding that the pathway arising from D1 striosomes connects directly to the substantia nigra, stimulating dopamine release and initiating movement.
“In the striosomes, we’ve found what is probably a mimic of the classical go/no-go pathways,” Graybiel says. “They’re like classic motor go/no-go pathways, but they don’t go to the motor output neurons of the basal ganglia. Instead, they go to the dopamine cells, which are so important to movement and motivation.”
Emotional decisions
The findings suggest that the classical model of how the striatum controls movement needs to be modified to include the role of these newly identified pathways. The researchers now hope to test their hypothesis that input related to motivation and emotion, which enters the striosomes from the cortex and the limbic system, influences dopamine levels in a way that can encourage or discourage action.
That dopamine release may be especially relevant for actions that induce anxiety or stress. In their 2015 study, Graybiel’s lab found that striosomes play a key role in making decisions that provoke high levels of anxiety; in particular, those that are high risk but may also have a big payoff.
“Ann Graybiel and colleagues have earlier found that the striosome is concerned with inhibiting dopamine neurons. Now they show unexpectedly that another type of striosomal neuron exerts the opposite effect and can signal reward. The striosomes can thus both up- or down-regulate dopamine activity, a very important discovery. Clearly, the regulation of dopamine activity is critical in our everyday life with regard to both movements and mood, to which the striosomes contribute,” says Sten Grillner, a professor of neuroscience at the Karolinska Institute in Sweden, who was not involved in the research.
Another possibility the researchers plan to explore is whether striosomes and matrix cells are arranged in modules that affect motor control of specific parts of the body.
“The next step is trying to isolate some of these modules, and by simultaneously working with cells that belong to the same module, whether they are in the matrix or striosomes, try to pinpoint how the striosomes modulate the underlying function of each of these modules,” Lazaridis says.
They also hope to explore how the striosomal circuits, which project to the same region of the brain that is ravaged by Parkinson’s disease, may influence that disorder.
The research was funded by the National Institutes of Health, the Saks-Kavanaugh Foundation, the William N. and Bernice E. Bumpus Foundation, Jim and Joan Schattinger, the Hock E. Tan and K. Lisa Yang Center for Autism Research, Robert Buxton, the Simons Foundation, the CHDI Foundation, and an Ellen Schapiro and Gerald Axelbaum Investigator BBRF Young Investigator Grant.
Astronomers detect ancient lonely quasars with murky originsThe quasars appear to have few cosmic neighbors, raising questions about how they first emerged more than 13 billion years ago.A quasar is the extremely bright core of a galaxy that hosts an active supermassive black hole at its center. As the black hole draws in surrounding gas and dust, it blasts out an enormous amount of energy, making quasars some of the brightest objects in the universe. Quasars have been observed as early as a few hundred million years after the Big Bang, and it’s been a mystery as to how these objects could have grown so bright and massive in such a short amount of cosmic time.
Scientists have proposed that the earliest quasars sprang from overly dense regions of primordial matter, which would also have produced many smaller galaxies in the quasars’ environment. But in a new MIT-led study, astronomers observed some ancient quasars that appear to be surprisingly alone in the early universe.
The astronomers used NASA’s James Webb Space Telescope (JWST) to peer back in time, more than 13 billion years, to study the cosmic surroundings of five known ancient quasars. They found a surprising variety in their neighborhoods, or “quasar fields.” While some quasars reside in very crowded fields with more than 50 neighboring galaxies, as all models predict, the remaining quasars appear to drift in voids, with only a few stray galaxies in their vicinity.
These lonely quasars are challenging physicists’ understanding of how such luminous objects could have formed so early on in the universe, without a significant source of surrounding matter to fuel their black hole growth.
“Contrary to previous belief, we find on average, these quasars are not necessarily in those highest-density regions of the early universe. Some of them seem to be sitting in the middle of nowhere,” says Anna-Christina Eilers, assistant professor of physics at MIT. “It’s difficult to explain how these quasars could have grown so big if they appear to have nothing to feed from.”
There is a possibility that these quasars may not be as solitary as they appear, but are instead surrounded by galaxies that are heavily shrouded in dust and therefore hidden from view. Eilers and her colleagues hope to tune their observations to try and see through any such cosmic dust, in order to understand how quasars grew so big, so fast, in the early universe.
Eilers and her colleagues report their findings in a paper appearing today in the Astrophysical Journal. The MIT co-authors include postdocs Rohan Naidu and Minghao Yue; Robert Simcoe, the Francis Friedman Professor of Physics and director of MIT’s Kavli Institute for Astrophysics and Space Research; and collaborators from institutions including Leiden University, the University of California at Santa Barbara, ETH Zurich, and elsewhere.
Galactic neighbors
The five newly observed quasars are among the oldest quasars observed to date. More than 13 billion years old, the objects are thought to have formed between 600 to 700 million years after the Big Bang. The supermassive black holes powering the quasars are a billion times more massive than the sun, and more than a trillion times brighter. Due to their extreme luminosity, the light from each quasar is able to travel over the age of the universe, far enough to reach JWST’s highly sensitive detectors today.
“It’s just phenomenal that we now have a telescope that can capture light from 13 billion years ago in so much detail,” Eilers says. “For the first time, JWST enabled us to look at the environment of these quasars, where they grew up, and what their neighborhood was like.”
The team analyzed images of the five ancient quasars taken by JWST between August 2022 and June 2023. The observations of each quasar comprised multiple “mosaic” images, or partial views of the quasar’s field, which the team effectively stitched together to produce a complete picture of each quasar’s surrounding neighborhood.
The telescope also took measurements of light in multiple wavelengths across each quasar’s field, which the team then processed to determine whether a given object in the field was light from a neighboring galaxy, and how far a galaxy is from the much more luminous central quasar.
“We found that the only difference between these five quasars is that their environments look so different,” Eilers says. “For instance, one quasar has almost 50 galaxies around it, while another has just two. And both quasars are within the same size, volume, brightness, and time of the universe. That was really surprising to see.”
Growth spurts
The disparity in quasar fields introduces a kink in the standard picture of black hole growth and galaxy formation. According to physicists’ best understanding of how the first objects in the universe emerged, a cosmic web of dark matter should have set the course. Dark matter is an as-yet unknown form of matter that has no other interactions with its surroundings other than through gravity.
Shortly after the Big Bang, the early universe is thought to have formed filaments of dark matter that acted as a sort of gravitational road, attracting gas and dust along its tendrils. In overly dense regions of this web, matter would have accumulated to form more massive objects. And the brightest, most massive early objects, such as quasars, would have formed in the web’s highest-density regions, which would have also churned out many more, smaller galaxies.
“The cosmic web of dark matter is a solid prediction of our cosmological model of the Universe, and it can be described in detail using numerical simulations,” says co-author Elia Pizzati, a graduate student at Leiden University. “By comparing our observations to these simulations, we can determine where in the cosmic web quasars are located.”
Scientists estimate that quasars would have had to grow continuously with very high accretion rates in order to reach the extreme mass and luminosities at the times that astronomers have observed them, fewer than 1 billion years after the Big Bang.
“The main question we’re trying to answer is, how do these billion-solar-mass black holes form at a time when the universe is still really, really young? It’s still in its infancy,” Eilers says.
The team’s findings may raise more questions than answers. The “lonely” quasars appear to live in relatively empty regions of space. If physicists’ cosmological models are correct, these barren regions signify very little dark matter, or starting material for brewing up stars and galaxies. How, then, did extremely bright and massive quasars come to be?
“Our results show that there’s still a significant piece of the puzzle missing of how these supermassive black holes grow,” Eilers says. “If there’s not enough material around for some quasars to be able to grow continuously, that means there must be some other way that they can grow, that we have yet to figure out.”
This research was supported, in part, by the European Research Council.
An exotic-materials researcher with the soul of an explorer Associate professor of physics Riccardo Comin never stops seeking uncharted territory.Riccardo Comin says the best part of his job as a physics professor and exotic-materials researcher is when his students come into his office to tell him they have new, interesting data.
“It’s that moment of discovery, that moment of awe, of revelation of something that’s outside of anything you know,” says Comin, the Class of 1947 Career Development Associate Professor of Physics. “That’s what makes it all worthwhile.”
Intriguing data energizes Comin because it can potentially grant access to an unexplored world. His team has discovered materials with quantum and other exotic properties, which could find a range of applications, such as handling the world’s exploding quantities of data, more precise medical imaging, and vastly increased energy efficiency — to name just a few. For Comin, who has always been somewhat of an explorer, new discoveries satisfy a kind of intellectual wanderlust.
As a small child growing up in the city of Udine in northeast Italy, Comin loved geography and maps, even drawing his own of imaginary cities and countries. He traveled literally, too, touring Europe with his parents; his father was offered free train travel as a project manager on large projects for Italian railroads.
Comin also loved numbers from an early age, and by about eighth grade would go to the public library to delve into math textbooks about calculus and analytical geometry that were far beyond what he was being taught in school. Later, in high school, Comin enjoyed being challenged by a math and physics teacher who in class would ask him questions about extremely advanced concepts.
“My classmates were looking at me like I was an alien, but I had a lot of fun,” Comin says.
Unafraid to venture alone into more rarefied areas of study, Comin nonetheless sought community, and appreciated the rapport he had with his teacher.
“He gave me the kind of interaction I was looking for, because otherwise it would have been just me and my books,” Comin says. “He helped transform an isolated activity into a social one. He made me feel like I had a buddy.”
By the end of his undergraduate studies at the University of Trieste, Comin says he decided on experimental physics, to have “the opportunity to explore and observe physical phenomena.”
He visited a nearby research facility that houses the Elettra Synchrotron to look for a research position where he could work on his undergraduate thesis, and became interested in all of the materials science research being conducted there. Drawn to community as well as the research, he chose a group that was investigating how the atoms and molecules in a liquid can rearrange themselves to become a glass.
“This one group struck me. They seemed to really enjoy what they were doing, and they had fun outside of work and enjoyed the outdoors,” Comin says. “They seemed to be a nice group of people to be part of. I think I cared more about the social environment than the specific research topic.”
By the time Comin was finishing his master’s, also in Trieste, and wanted to get a PhD, his focus had turned to electrons inside a solid rather than the behavior of atoms and molecules. Having traveled “literally almost everywhere in Europe,” Comin says he wanted to experience a different research environment outside of Europe.
He told his academic advisor he wanted to go to North America and was connected with Andrea Damascelli, the Canada Research Chair in Electronic Structure of Quantum Materials at the University of British Columbia, who was working on high-temperature superconductors. Comin says he was fascinated by the behavior of the electrons in the materials Damascelli and his group were studying.
“It’s almost like a quantum choreography, particles that dance together” rather than moving in many different directions, Comin says.
Comin’s subsequent postdoctoral work at the University of Toronto, focusing on optoelectronic materials — which can interact with photons and electrical energy — ignited his passion for connecting a material’s properties to its functionality and bridging the gap between fundamental physics and real-world applications.
Since coming to MIT in 2016, Comin has continued to delight in the behavior of electrons. He and Joe Checkelsky, associate professor of physics, had a breakthrough with a new class of materials in which electrons, very atypically, are nearly stationary.
Such materials could be used to explore zero energy loss, such as from power lines, and new approaches to quantum computing.
“It’s a very peculiar state of matter,” says Comin. “Normally, electrons are just zapping around. If you put an electron in a crystalline environment, what that electron will want to do is hop around, explore its neighbors, and basically be everywhere at the same time.”
The more sedentary electrons occurred in materials where a structure of interlaced triangles and hexagons tended to trap the electrons on the hexagons and, because the electrons all have the same energy, they create what’s called an electronic flat band, referring to the pattern that is created when they are measured. Their existence was predicted theoretically, but they had not been observed.
Comin says he and his colleagues made educated guesses on where to find flat bands, but they were elusive. After three years of research, however, they had a breakthrough.
“We put a sample material in an experimental chamber, we aligned the sample to do the experiment and started the measurement and, literally, five to 10 minutes later, we saw this beautiful flat band on the screen,” Comin says. “It was so clear, like this thing was basically screaming, How could you not find me before?
“That started off a whole area of research that is growing and growing — and a new direction in our field.”
Comin’s later research into certain two-dimensional materials with the thickness of single atoms and an internal structural feature of chirality, or right-handedness or left-handedness similar to how a spiral has a twist in one direction or the other, has yielded another new realm to explore.
By controlling the chirality, “there are interesting prospects of realizing a whole new class of devices” that could store information in a way that’s more robust and much more energy-efficient than current methods, says Comin, who is affiliated with MIT’s Materials Research Laboratory. Such devices would be especially valuable as the amount of data available generally and technologies like artificial intelligence grow exponentially.
While investigating these previously unknown properties of certain materials, Comin is characteristically adventurous in his pursuit.
“I embrace the randomness that nature throws at you,” he says. “It appears random, but there could be something behind it, so we try variations, switch things around, see what nature serves you. Much of what we discover is due to luck — and the rest boils down to a mix of knowledge and intuition to recognize when we’re seeing something new, something that’s worth exploring.”
Q&A: How the Europa Clipper will set cameras on a distant icy moonMIT Research Scientist Jason Soderblom describes how the NASA mission will study the geology and composition of the surface of Jupiter’s water-rich moon and assess its astrobiological potential.With its latest space mission successfully launched, NASA is set to return for a close-up investigation of Jupiter’s moon Europa. Yesterday at 12:06 p.m. EDT, the Europa Clipper lifted off via SpaceX Falcon Heavy rocket on a mission that will take a close look at Europa’s icy surface. Five years from now, the spacecraft will visit the moon, which hosts a water ocean covered by a water-ice shell. The spacecraft’s mission is to learn more about the composition and geology of the moon’s surface and interior and to assess its astrobiological potential. Because of Jupiter’s intense radiation environment, Europa Clipper will conduct a series of flybys, with its closest approach bringing it within just 16 miles of Europa’s surface.
MIT Department of Earth, Atmospheric and Planetary Sciences (EAPS) Research Scientist Jason Soderblom is a co-investigator on two of the spacecraft’s instruments: the Europa Imaging System and the Mapping Imaging Spectrometer for Europa. Over the past nine years, he and his fellow team members have been building imaging and mapping instruments to study Europa’s surface in detail to gain a better understanding of previously seen geologic features, as well as the chemical composition of the materials that are present. Here, he describes the mission's primary plans and goals.
Q: What do we currently know about Europa’s surface?
A: We know from NASA Galileo mission data that the surface crust is relatively thin, but we don’t know how thin it is. One of the goals of the Europa Clipper mission is to measure the thickness of that ice shell. The surface is riddled with fractures that indicate tectonism is actively resurfacing the moon. Its crust is primarily composed of water ice, but there are also exposures of non-ice material along these fractures and ridges that we believe include material coming up from within Europa.
One of the things that makes investigating the materials on the surface more difficult is the environment. Jupiter is a significant source of radiation, and Europa is relatively close to Jupiter. That radiation modifies the materials on the surface; understanding that radiation damage is a key component to understanding the composition.
This is also what drives the clipper-style mission and gives the mission its name: we clip by Europa, collect data, and then spend the majority of our time outside of the radiation environment. That allows us time to download the data, analyze it, and make plans for the next flyby.
Q: Did that pose a significant challenge when it came to instrument design?
A: Yes, and this is one of the reasons that we're just now returning to do this mission. The concept of this mission came about around the time of the Galileo mission in the late 1990s, so it's been roughly 25 years since scientists first wanted to carry out this mission. A lot of that time has been figuring out how to deal with the radiation environment.
There's a lot of tricks that we've been developing over the years. The instruments are heavily shielded, and lots of modeling has gone into figuring exactly where to put that shielding. We've also developed very specific techniques to collect data. For example, by taking a whole bunch of short observations, we can look for the signature of this radiation noise, remove it from the little bits of data here and there, add the good data together, and end up with a low-radiation-noise observation.
Q: You're involved with the two different imaging and mapping instruments: the Europa Imaging System (EIS) and the Mapping Imaging Spectrometer for Europa (MISE). How are they different from each other?
A: The camera system [EIS] is primarily focused on understanding the physics and the geology that's driving processes on the surface, looking for: fractured zones; regions that we refer to as chaos terrain, where it looks like icebergs have been suspended in a slurry of water and have jumbled around and mixed and twisted; regions where we believe the surface is colliding and subduction is occurring, so one section of the surface is going beneath the other; and other regions that are spreading, so new surface is being created like our mid-ocean ridges on Earth.
The spectrometer’s [MISE] primary function is to constrain the composition of the surface. In particular, we're really interested in sections where we think liquid water might have come to the surface. Understanding what material is from within Europa and what material is being deposited from external sources is also important, and separating that is necessary to understand the composition of those coming from Europa and using that to learn about the composition of the subsurface ocean.
There is an intersection between those two, and that's my interest in the mission. We have color imaging with our imaging system that can provide some crude understanding of the composition, and there is a mapping component to our spectrometer that allows us to understand how the materials that we're detecting are physically distributed and correlate with the geology. So there's a way to examine the intersection of those two disciplines — to extrapolate the compositional information derived from the spectrometer to much higher resolutions using the camera, and to extrapolate the geological information that we learn from the camera to the compositional constraints from the spectrometer.
Q: How do those mission goals align with the research that you've been doing here at MIT?
A: One of the other major missions that I've been involved with was the Cassini mission, primarily working with the Visual and Infrared Spectrometer team to understand the geology and composition of Saturn's moon Titan. That instrument is very similar to the MISE instrument, both in function and in science objective, and so there's a very strong connection between that and the Europa Clipper mission. For another mission, for which I’m leading the camera team, is working to retrieve a sample of a comet, and my primary function on that mission is understanding the geology of the cometary surface.
Q: What are you most excited about learning from the Europa Clipper mission?
A: I'm most fascinated with some of these very unique geologic features that we see on the surface of Europa, understanding the composition of the material that is involved, and the processes that are driving those features. In particular, the chaos terrains and the fractures that we see on the surface.
Q: It's going to be a while before the spacecraft finally reaches Europa. What work needs to be done in the meantime?
A: A key component of this mission will be the laboratory work here on Earth, expanding our spectral libraries so that when we collect a spectrum of Europa's surface, we can compare that to laboratory measurements. We are also in the process of developing a number of models to allow us to, for example, understand how a material might process and change starting in the ocean and working its way up through fractures and eventually to the surface. Developing these models now is an important piece before we collect these data, then we can make corrections and get improved observations as the mission progresses. Making the best and most efficient use of the spacecraft resources requires an ability to reprogram and refine observations in real-time.
Model reveals why debunking election misinformation often doesn’t workThe new study also identifies factors that can make these efforts more successful.When an election result is disputed, people who are skeptical about the outcome may be swayed by figures of authority who come down on one side or the other. Those figures can be independent monitors, political figures, or news organizations. However, these “debunking” efforts don’t always have the desired effect, and in some cases, they can lead people to cling more tightly to their original position.
Neuroscientists and political scientists at MIT and the University of California at Berkeley have now created a computational model that analyzes the factors that help to determine whether debunking efforts will persuade people to change their beliefs about the legitimacy of an election. Their findings suggest that while debunking fails much of the time, it can be successful under the right conditions.
For instance, the model showed that successful debunking is more likely if people are less certain of their original beliefs and if they believe the authority is unbiased or strongly motivated by a desire for accuracy. It also helps when an authority comes out in support of a result that goes against a bias they are perceived to hold: for example, Fox News declaring that Joseph R. Biden had won in Arizona in the 2020 U.S. presidential election.
“When people see an act of debunking, they treat it as a human action and understand it the way they understand human actions — that is, as something somebody did for their own reasons,” says Rebecca Saxe, the John W. Jarve Professor of Brain and Cognitive Sciences, a member of MIT’s McGovern Institute for Brain Research, and the senior author of the study. “We’ve used a very simple, general model of how people understand other people’s actions, and found that that’s all you need to describe this complex phenomenon.”
The findings could have implications as the United States prepares for the presidential election taking place on Nov. 5, as they help to reveal the conditions that would be most likely to result in people accepting the election outcome.
MIT graduate student Setayesh Radkani is the lead author of the paper, which appears today in a special election-themed issue of the journal PNAS Nexus. Marika Landau-Wells PhD ’18, a former MIT postdoc who is now an assistant professor of political science at the University of California at Berkeley, is also an author of the study.
Modeling motivation
In their work on election debunking, the MIT team took a novel approach, building on Saxe’s extensive work studying “theory of mind” — how people think about the thoughts and motivations of other people.
As part of her PhD thesis, Radkani has been developing a computational model of the cognitive processes that occur when people see others being punished by an authority. Not everyone interprets punitive actions the same way, depending on their previous beliefs about the action and the authority. Some may see the authority as acting legitimately to punish an act that was wrong, while others may see an authority overreaching to issue an unjust punishment.
Last year, after participating in an MIT workshop on the topic of polarization in societies, Saxe and Radkani had the idea to apply the model to how people react to an authority attempting to sway their political beliefs. They enlisted Landau-Wells, who received her PhD in political science before working as a postdoc in Saxe’s lab, to join their effort, and Landau suggested applying the model to debunking of beliefs regarding the legitimacy of an election result.
The computational model created by Radkani is based on Bayesian inference, which allows the model to continually update its predictions of people’s beliefs as they receive new information. This approach treats debunking as an action that a person undertakes for his or her own reasons. People who observe the authority’s statement then make their own interpretation of why the person said what they did. Based on that interpretation, people may or may not change their own beliefs about the election result.
Additionally, the model does not assume that any beliefs are necessarily incorrect or that any group of people is acting irrationally.
“The only assumption that we made is that there are two groups in the society that differ in their perspectives about a topic: One of them thinks that the election was stolen and the other group doesn’t,” Radkani says. “Other than that, these groups are similar. They share their beliefs about the authority — what the different motives of the authority are and how motivated the authority is by each of those motives.”
The researchers modeled more than 200 different scenarios in which an authority attempts to debunk a belief held by one group regarding the validity of an election outcome.
Each time they ran the model, the researchers altered the certainty levels of each group’s original beliefs, and they also varied the groups’ perceptions of the motivations of the authority. In some cases, groups believed the authority was motivated by promoting accuracy, and in others they did not. The researchers also altered the groups’ perceptions of whether the authority was biased toward a particular viewpoint, and how strongly the groups believed in those perceptions.
Building consensus
In each scenario, the researchers used the model to predict how each group would respond to a series of five statements made by an authority trying to convince them that the election had been legitimate. The researchers found that in most of the scenarios they looked at, beliefs remained polarized and in some cases became even further polarized. This polarization could also extend to new topics unrelated to the original context of the election, the researchers found.
However, under some circumstances, the debunking was successful, and beliefs converged on an accepted outcome. This was more likely to happen when people were initially more uncertain about their original beliefs.
“When people are very, very certain, they become hard to move. So, in essence, a lot of this authority debunking doesn’t matter,” Landau-Wells says. “However, there are a lot of people who are in this uncertain band. They have doubts, but they don’t have firm beliefs. One of the lessons from this paper is that we’re in a space where the model says you can affect people’s beliefs and move them towards true things.”
Another factor that can lead to belief convergence is if people believe that the authority is unbiased and highly motivated by accuracy. Even more persuasive is when an authority makes a claim that goes against their perceived bias — for instance, Republican governors stating that elections in their states had been fair even though the Democratic candidate won.
As the 2024 presidential election approaches, grassroots efforts have been made to train nonpartisan election observers who can vouch for whether an election was legitimate. These types of organizations may be well-positioned to help sway people who might have doubts about the election’s legitimacy, the researchers say.
“They’re trying to train to people to be independent, unbiased, and committed to the truth of the outcome more than anything else. Those are the types of entities that you want. We want them to succeed in being seen as independent. We want them to succeed as being seen as truthful, because in this space of uncertainty, those are the voices that can move people toward an accurate outcome,” Landau-Wells says.
The research was funded, in part, by the Patrick J. McGovern Foundation and the Guggenheim Foundation.
Tiny magnetic discs offer remote brain stimulation without transgenesThe devices could be a useful tool for biomedical research, and possible clinical use in the future.Novel magnetic nanodiscs could provide a much less invasive way of stimulating parts of the brain, paving the way for stimulation therapies without implants or genetic modification, MIT researchers report.
The scientists envision that the tiny discs, which are about 250 nanometers across (about 1/500 the width of a human hair), would be injected directly into the desired location in the brain. From there, they could be activated at any time simply by applying a magnetic field outside the body. The new particles could quickly find applications in biomedical research, and eventually, after sufficient testing, might be applied to clinical uses.
The development of these nanoparticles is described in the journal Nature Nanotechnology, in a paper by Polina Anikeeva, a professor in MIT’s departments of Materials Science and Engineering and Brain and Cognitive Sciences, graduate student Ye Ji Kim, and 17 others at MIT and in Germany.
Deep brain stimulation (DBS) is a common clinical procedure that uses electrodes implanted in the target brain regions to treat symptoms of neurological and psychiatric conditions such as Parkinson’s disease and obsessive-compulsive disorder. Despite its efficacy, the surgical difficulty and clinical complications associated with DBS limit the number of cases where such an invasive procedure is warranted. The new nanodiscs could provide a much more benign way of achieving the same results.
Over the past decade other implant-free methods of producing brain stimulation have been developed. However, these approaches were often limited by their spatial resolution or ability to target deep regions. For the past decade, Anikeeva’s Bioelectronics group as well as others in the field used magnetic nanomaterials to transduce remote magnetic signals into brain stimulation. However, these magnetic methods relied on genetic modifications and can’t be used in humans.
Since all nerve cells are sensitive to electrical signals, Kim, a graduate student in Anikeeva’s group, hypothesized that a magnetoelectric nanomaterial that can efficiently convert magnetization into electrical potential could offer a path toward remote magnetic brain stimulation. Creating a nanoscale magnetoelectric material was, however, a formidable challenge.
Kim synthesized novel magnetoelectric nanodiscs and collaborated with Noah Kent, a postdoc in Anikeeva’s lab with a background in physics who is a second author of the study, to understand the properties of these particles.
The structure of the new nanodiscs consists of a two-layer magnetic core and a piezoelectric shell. The magnetic core is magnetostrictive, which means it changes shape when magnetized. This deformation then induces strain in the piezoelectric shell which produces a varying electrical polarization. Through the combination of the two effects, these composite particles can deliver electrical pulses to neurons when exposed to magnetic fields.
One key to the discs’ effectiveness is their disc shape. Previous attempts to use magnetic nanoparticles had used spherical particles, but the magnetoelectric effect was very weak, says Kim. This anisotropy enhances magnetostriction by over a 1000-fold, adds Kent.
The team first added their nanodiscs to cultured neurons, which allowed then to activate these cells on demand with short pulses of magnetic field. This stimulation did not require any genetic modification.
They then injected small droplets of magnetoelectric nanodiscs solution into specific regions of the brains of mice. Then, simply turning on a relatively weak electromagnet nearby triggered the particles to release a tiny jolt of electricity in that brain region. The stimulation could be switched on and off remotely by the switching of the electromagnet. That electrical stimulation “had an impact on neuron activity and on behavior,” Kim says.
The team found that the magnetoelectric nanodiscs could stimulate a deep brain region, the ventral tegmental area, that is associated with feelings of reward.
The team also stimulated another brain area, the subthalamic nucleus, associated with motor control. “This is the region where electrodes typically get implanted to manage Parkinson’s disease,” Kim explains. The researchers were able to successfully demonstrate the modulation of motor control through the particles. Specifically, by injecting nanodiscs only in one hemisphere, the researchers could induce rotations in healthy mice by applying magnetic field.
The nanodiscs could trigger the neuronal activity comparable with conventional implanted electrodes delivering mild electrical stimulation. The authors achieved subsecond temporal precision for neural stimulation with their method yet observed significantly reduced foreign body responses as compared to the electrodes, potentially allowing for even safer deep brain stimulation.
The multilayered chemical composition and physical shape and size of the new multilayered nanodiscs is what made precise stimulation possible.
While the researchers successfully increased the magnetostrictive effect, the second part of the process, converting the magnetic effect into an electrical output, still needs more work, Anikeeva says. While the magnetic response was a thousand times greater, the conversion to an electric impulse was only four times greater than with conventional spherical particles.
“This massive enhancement of a thousand times didn’t completely translate into the magnetoelectric enhancement,” says Kim. “That’s where a lot of the future work will be focused, on making sure that the thousand times amplification in magnetostriction can be converted into a thousand times amplification in the magnetoelectric coupling.”
What the team found, in terms of the way the particles’ shapes affects their magnetostriction, was quite unexpected. “It’s kind of a new thing that just appeared when we tried to figure out why these particles worked so well,” says Kent.
Anikeeva adds: “Yes, it’s a record-breaking particle, but it’s not as record-breaking as it could be.” That remains a topic for further work, but the team has ideas about how to make further progress.
While these nanodiscs could in principle already be applied to basic research using animal models, to translate them to clinical use in humans would require several more steps, including large-scale safety studies, “which is something academic researchers are not necessarily most well-positioned to do,” Anikeeva says. “When we find that these particles are really useful in a particular clinical context, then we imagine that there will be a pathway for them to undergo more rigorous large animal safety studies.”
The team included researchers affiliated with MIT’s departments of Materials Science and Engineering, Electrical Engineering and Computer Science, Chemistry, and Brain and Cognitive Sciences; the Research Laboratory of Electronics; the McGovern Institute for Brain Research; and the Koch Institute for Integrative Cancer Research; and from the Friedrich-Alexander University of Erlangen, Germany. The work was supported, in part, by the National Institutes of Health, the National Center for Complementary and Integrative Health, the National Institute for Neurological Disorders and Stroke, the McGovern Institute for Brain Research, and the K. Lisa Yang and Hock E. Tan Center for Molecular Therapeutics in Neuroscience.