Transistors, the building blocks of modern electronics, are typically made of silicon. Because it’s a semiconductor, this material can control the flow of electricity in a circuit. But silicon has fundamental physical limits that restrict how compact and energy-efficient a transistor can be.

MIT researchers have now replaced silicon with a magnetic semiconductor, creating a magnetic transistor that could enable smaller, faster, and more energy-efficient circuits. The material’s magnetism strongly influences its electronic behavior, leading to more efficient control of the flow of electricity. 

The team used a novel magnetic material and an optimization process that reduces the material’s defects, which boosts the transistor’s performance.

The material’s unique magnetic properties also allow for transistors with built-in memory, which would simplify circuit design and unlock new applications for high-performance electronics.

“People have known about magnets for thousands of years, but there are very limited ways to incorporate magnetism into electronics. We have shown a new way to efficiently utilize magnetism that opens up a lot of possibilities for future applications and research,” says Chung-Tao Chou, an MIT graduate student in the departments of Electrical Engineering and Computer Science (EECS) and Physics, and co-lead author of a paper on this advance.

Chou is joined on the paper by co-lead author Eugene Park, a graduate student in the Department of Materials Science and Engineering (DMSE); Julian Klein, a DMSE research scientist; Josep Ingla-Aynes, a postdoc in the MIT Plasma Science and Fusion Center; Jagadeesh S. Moodera, a senior research scientist in the Department of Physics; and senior authors Frances Ross, TDK Professor in DMSE; and Luqiao Liu, an associate professor in EECS, and a member of the Research Laboratory of Electronics; as well as others at the University of Chemistry and Technology in Prague. The paper appears today in Physical Review Letters.

Overcoming the limits

In an electronic device, silicon semiconductor transistors act like tiny light switches that turn a circuit on and off, or amplify weak signals in a communication system. They do this using a small input voltage.

But a fundamental physical limit of silicon semiconductors prevents a transistor from operating below a certain voltage, which hinders its energy efficiency.

To make more efficient electronics, researchers have spent decades working toward magnetic transistors that utilize electron spin to control the flow of electricity. Electron spin is a fundamental property that enables electrons to behave like tiny magnets.

So far, scientists have mostly been limited to using certain magnetic materials. These lack the favorable electronic properties of semiconductors, constraining device performance.

“In this work, we combine magnetism and semiconductor physics to realize useful spintronic devices,” Liu says.

The researchers replace the silicon in the surface layer of a transistor with chromium sulfur bromide, a two-dimensional material that acts as a magnetic semiconductor.

Due to the material’s structure, researchers can switch between two magnetic states very cleanly. This makes it ideal for use in a transistor that smoothly switches between “on” and “off.”

“One of the biggest challenges we faced was finding the right material. We tried many other materials that didn’t work,” Chou says.

They discovered that changing these magnetic states modifies the material’s electronic properties, enabling low-energy operation. And unlike many other 2D materials, chromium sulfur bromide remains stable in air.

To make a transistor, the researchers pattern electrodes onto a silicon substrate, then carefully align and transfer the 2D material on top. They use tape to pick up a tiny piece of material, only a few tens of nanometers thick, and place it onto the substrate.

“A lot of researchers will use solvents or glue to do the transfer, but transistors require a very clean surface. We eliminate all those risks by simplifying this step,” Chou says.

Leveraging magnetism

This lack of contamination enables their device to outperform existing magnetic transistors. Most others can only create a weak magnetic effect, changing the flow of current by a few percent or less. Their new transistor can switch or amplify the electric current by a factor of 10.

They use an external magnetic field to change the magnetic state of the material, switching the transistor using significantly less energy than would usually be required.

The material also allows them to control the magnetic states with electric current. This is important because engineers cannot apply magnetic fields to individual transistors in an electronic device. They need to control each one electrically.

The material’s magnetic properties could also enable transistors with built-in memory, simplifying the design of logic or memory circuits.

A typical memory device has a magnetic cell to store information and a transistor to read it out. Their method can combine both into one magnetic transistor.

“Now, not only are transistors turning on and off, they are also remembering information. And because we can switch the transistor with greater magnitude, the signal is much stronger so we can read out the information faster, and in a much more reliable way,” Liu says.

Building on this demonstration, the researchers plan to further study the use of electrical current to control the device. They are also working to make their method scalable so they can fabricate arrays of transistors.

This research was supported, in part, by the Semiconductor Research Corporation, the U.S. Defense Advanced Research Projects Agency (DARPA), the U.S. National Science Foundation (NSF), the U.S. Department of Energy, the U.S. Army Research Office, and the Czech Ministry of Education, Youth, and Sports. The work was partially carried out at the MIT.nano facilities.

For decades, scientists with big questions about biology have found answers in a tiny worm. That worm — a millimeter-long creature called Caenorhabditis elegans — has helped researchers uncover fundamental features of how cells and organisms work. The impact of that work is enormous: Discoveries made using C. elegans have been recognized with four Nobel Prizes and have led to the development of new treatments for human disease.

In a perspective piece published in the November 2025 issue of the journal PNAS, 11 biologists including Robert Horvitz, the David H. Koch (1962) Professor of Biology at MIT, celebrate Nobel Prize-winning advances made through research in C. elegans. The authors discuss how that work has led to advances for human health, and highlight how a uniquely collaborative community among worm researchers has fueled the field.

MIT scientists are well represented in that community: The prominent worm biologists who coauthored the PNAS paper include former MIT graduate students Andrew Fire PhD ’83 and Paul Sternberg PhD ’84, now at Stanford University and Caltech, respectively; and two past members of Horvitz’s lab, Victor Ambros ’75, PhD ’79, who is now at the University of Massachusetts Medical School, and former postdoc Gary Ruvkun of Massachusetts General Hospital. Ann Rougvie at the University of Minnesota is the paper’s corresponding author.

“This tiny worm is beautiful — elegant both in its appearance and in its many contributions to our understanding of the biological universe in which we live,” says Horvitz, who in 2002 was awarded the Nobel Prize in Physiology or Medicine, along with colleagues Sydney Brenner and John Sulston, for discoveries that helped explain how genes regulate programmed cell death and organ development. 

Early worm discoveries

Those discoveries were among the early successes in C. elegans research, made by pioneering scientists who recognized the power of the microscopic roundworm. C. elegans offers many advantages for researchers: The worms are easy to grow and maintain in labs; their transparent bodies make cells and internal processes readily visible under a microscope; they are cellularly very simple (e.g., they have only 302 nerve cells, compared with about 100 billion in a human) and their genomes can be readily manipulated to study gene function.

Most importantly, many of the molecules and processes that operate in C. elegans have been retained throughout evolution, meaning discoveries made using the worm can have direct relevance to other organisms, including humans. 

“Many aspects of biology are ancient and evolutionarily conserved,” Horvitz, who is also a member of MIT’s McGovern Institute for Brain Research and Koch Institute for Integrative Cancer Research, as well as an investigator at the Howard Hughes Medical Institute. “Such shared mechanisms can be most readily revealed by analyzing organisms that are highly tractable in the laboratory.”

In the 1960s, Brenner, a molecular biologist who was curious about how animals’ nervous systems develop and function, recognized that C. elegans offered unique opportunities to study these processes. Once he began developing the worm into a model for laboratory studies, it did not take long for other biologists to join him to take advantage of the new system.

In the 1970s, the unique features of the worm allowed Sulston to track the transformation of a fertilized egg into an adult animal, tracing the origins of each of the adult worm’s 959 cells. His studies revealed that in every developing worm, cells divide and mature in predictable ways. He also learned that some of the cells created during development do not survive into adulthood, and are instead eliminated by a process termed programmed cell death.

By seeking mutations that perturbed the process of programmed cell death, Horvitz and his colleagues identified key regulators of that process, which is sometimes referred to as apoptosis. These regulators, which both promote and oppose apoptosis, turned out to be vital for programmed cell death across the animal kingdom.

In humans, apoptosis shapes developing organs, refines brain circuits, and optimizes other tissue structures. It also modulates our immune systems and eliminates cells that are in danger of becoming cancerous. The human version of CED-9, the anti-apoptotic regulator that Horvitz’s team discovered in worms, is BCL-2. Researchers have shown that activating apoptotic cell death by blocking BCL-2 is an effective treatment for certain blood cancers. Today, researchers are also exploring new ways of treating immune disorders and neurodegenerative disease by manipulating apoptosis pathways.

Collaborative worm community

Horvitz and his colleagues’ discoveries about apoptosis helped demonstrate that understanding C. elegans biology has direct relevance to human biology and disease. Since then, a vibrant and closely connected community of worm biologists — including many who trained in Horvitz’s lab — has continued to carry out impactful work. In their PNAS article, Horvitz and his coauthors highlight that early work, as well as the Nobel Prize-winning work of:

• Andrew Fire and Craig Mello, whose discovery of an RNA-based system of gene silencing led to powerful new tools to manipulate gene activity. The innate process they discovered in worms, known as RNA interference, is now used as the basis of six FDA-approved therapeutics for genetic disorders, silencing faulty genes to stop their harmful effects.
• Martin Chalfie, who used a fluorescent protein made by jellyfish to visualize and track specific cells in C. elegans, helping launch the development of a set of tools that transformed biologists’ ability to observe molecules and processes that are important for both health and disease.
• Victor Ambros and Gary Ruvkun, who discovered a class of molecules called microRNAs that regulate gene activity not just in worms, but in all multicellular organisms. This prize-winning work was started when Ambros and Ruvkun were postdocs in Horvitz’s lab. Humans rely on more than 1,000 microRNAs to ensure our genes are used at the right times and places. Disruptions to microRNAs have been linked to neurological disorders, cancer, cardiovascular disease, and autoimmune disease, and researchers are now exploring how these small molecules might be used for diagnosis or treatment.

Horvitz and his coauthors stress that while the worm itself made these discoveries possible, so too did a host of resources that facilitate collaboration within the worm community and enable its scientists to build upon the work of others. Scientists who study C. elegans have embraced this open, collaborative spirit since the field’s earliest days, Horvitz says, citing the Worm Breeder’s Gazette, an early newsletter where scientists shared their observations, methods, and ideas.

Today, scientists who study C. elegans — whether the organism is the centerpiece of their lab or they are looking to supplement studies of other systems — contribute to and rely on online resources like WormAtlas and WormBase, as well as the Caenorhabditis Genetics Center, to share data and genetic tools. Horvitz says these resources have been crucial to his own lab’s work; his team uses them every day.

Just as molecules and processes discovered in C. elegans have pointed researchers toward important pathways in human cells, the worm has also been a vital proving ground for developing methods and approaches later deployed to study more complex organisms. For example, C. elegans, with its 302 neurons, was the first animal for which neuroscientists successfully mapped all of the connections of the nervous system. The resulting wiring diagram, or connectome, has guided countless experiments exploring how neurons work together to process information and control behavior. Informed by both the power and limitations of the C. elegans’ connectome, scientists are now mapping more complex circuitry, such as the 139,000-neuron brain of the fruit fly, whose connectome was completed in 2024.

C. elegans remains a mainstay of biological research, including in neuroscience. Scientists worldwide are using the worm to explore new questions about neural circuits, neurodegeneration, development, and disease. Horvitz’s lab continues to turn to C. elegans to investigate the genes that control animal development and behavior. His team is now using the worm to explore how animals develop a sense of time and transmit that information to their offspring.

Also at MIT, Steven Flavell’s team in the Department of Brain and Cognitive Sciences and The Picower Institute for Learning and Memory is using the worm to investigate how neural connectivity, activity, and modulation integrate internal states, such as hunger, with sensory information, such as the smell of food, to produce sometimes long-lasting behaviors. (Flavell is Horvitz’s academic grandson, as Flavell trained with one of Horvitz’s postdoctoral trainees.)

As new technologies accelerate the pace of scientific discovery, Horvitz and his colleagues are confident that the humble worm will bring more unexpected insights.

The James M. and Cathleen D. Stone Center on Inequality and Shaping the Future of Work officially launched on Nov. 3, 2025, bringing together scholars, policymakers, and practitioners to explore critical questions about economic opportunity, technology, and democracy.

Co-directed by MIT professors Daron Acemoglu, David Autor, and Simon Johnson, the new Stone Center analyzes the forces that contribute to growing income and wealth inequality through the erosion of job quality and labor market opportunities for workers without a college degree. The center identifies innovative ways to move the economy onto a more equitable trajectory.

MIT Provost Anantha Chandrakasan opened the launch event by emphasizing the urgency and importance of the center's mission. “As artificial intelligence tools become more powerful, and as they are deployed more broadly,” he said, “we will need to strive to ensure that people from all kinds of backgrounds can find opportunity in the economy.”

Here are some of the key takeaways from participants in the afternoon’s discussions on wealth inequality, liberalism, and pro-worker AI.

Wealth inequality is driven by private business and public policy

Owen Zidar of Princeton University stressed that owners of businesses like car dealerships, construction firms, and franchises make up a significant portion of the top 1 percent. “For every public company CEO that gets a lot of attention,” he explained, “there are a thousand private business owners who have at least $25 million in wealth.” These business owners have outsized political influence through overrepresentation, lobbying, and donations.

Atif Mian of Princeton University connected high inequality to the U.S. debt crisis, arguing that massive savings at the top aren’t being channeled into productive investment. Instead, falling interest rates push the government to run increasingly large fiscal deficits.

To mitigate wealth inequality, speakers highlighted policy proposals including rolling back the 20 percent deduction for private business owners and increasing taxes on wealth.

However, policies must be carefully designed. Antoinette Schoar of the MIT Sloan School of Management explained how mortgage subsidy policies after the 2008 financial crisis actually worsened inequality by disadvantaging poorer potential homeowners.

Governments must provide basic public goods and economic security

Marc Dunkelman of the Watson School of International and Public Affairs at Brown University identified excessive red tape as a key problem for modern liberal democracy. “We can’t build high-speed rail. You can’t build enough housing,” he explained. “That spurs ordinary people who want government to work into the populist camp. We did this to ourselves.”

Josh Cohen of Apple University/the University of California at Berkeley emphasized that liberalism must deliver shared prosperity and fair opportunities, not just protect individual freedoms. When people lack economic security, they may turn to leaders who abandon liberal principles altogether.

Liberal democracy needs to adapt while keeping its core values

Helena Rosenblatt Dhar of the City University of New York Graduate Center noted that liberalism and democracy have not always been allies. Historically, “civil equality was very important, but not political equality,” she said. “Liberals were very wary of the masses.”

Speakers emphasized that liberalism’s challenge today is maintaining its commitments to limiting authoritarian power and protecting fundamental freedoms, while addressing its failures.

Doing so, in Dunkelman’s view, would mean working to “eliminate the sowing [of] the seeds of populism by making government properly balance individual rights and the will of the many.”

People-centric politics requires regulating social media

In his keynote at the launch, U.S. Representative Jake Auchincloss (Massachusetts 4th District) connected these notions of government effectiveness and public trust to the influence of technology. He emphasized the need to regulate social media platforms.

“In my opinion, media is upstream of culture, which is upstream of politics,” he said. “If we want a better culture, and certainly if we want a better politics, we need a better media.”

Auchincloss proposed that regulation should include holding social media companies liable for content and banning targeted advertising to minors.

He also echoed the urgency and importance of the center’s research agenda, particularly to understand whether AI will augment or replace labor.

“My bias has always been: Technology creates more jobs,” he said. “Maybe it’s different this time. Maybe I’m wrong.”

Augmentation is key to pro-worker AI — but it may require alternative AI architectures

Stone Center co-director Daron Acemoglu argued that expanding what humans can do, rather than automating their tasks, is essential for achieving pro-worker AI.

However, Acemoglu cautioned that this won’t happen by itself, noting that the business models of tech companies and their focus on artificial general intelligence are not aligned with a pro-worker vision for AI. This vision may require public investment in alternative AI architectures focused on “domain-specific, reliable knowledge.”

Ethan Mollick of the Wharton School of the University of Pennsylvania noted that AI labs are explicitly trying to “replace people at everything” and are “absolutely convinced that they can do this in the very near term.”

Meanwhile, companies have “no model for AI adoption,” Mollick explained. “There is absolute confusion.” Even so, “there’s enough money at stake [that] the machine keeps moving forward,” underscoring the urgency of intervention.

In a glimpse of what such intervention could look like, Zana Buçinca of Microsoft shared research findings that accounting for workers’ values and cognition in AI design can enable better complementarity.

“The impact of AI on human work is not destiny,” she emphasized. “It’s design.”

When the MIT Human Insight Collaborative (MITHIC) launched in fall 2024, it was designed to elevate scholars at the frontiers of human-centered research and education, and to provide them with resources to pursue their most innovative and ambitious ideas. 

At the inaugural MITHIC Annual Event on Nov. 17, 2025, faculty from across the Institute shared the progress and impact of the projects they’ve advanced this past year with support from the presidential initiative. 

In opening remarks, MIT President Sally Kornbluth noted the “incredible range of opportunities for faculty and students to ask new questions and arrive at better, bolder, and more nuanced answers, grounded in the wisdom of the humanities, arts, and social sciences,” that MITHIC has sparked in its first year. 

Kornbluth highlighted the Living Climate Futures Lab as an example of the kind of work MITHIC was designed to support. “The lab works with people in communities from Massachusetts to Mongolia who are grappling with the impacts of climate change on their daily lives — on health and food security, housing, and jobs,” she said. The initiative, which was the focus of a panel discussion during the event, received MITHIC’s inaugural Faculty-Driven Initiative (FDI) seed grant.

“Like all the projects that MITHIC supports, the Living Climate Futures Lab also embodies MIT’s singular brand of excellence: collaborative, hands-on, and is deeply relevant to the world and the people around us,” added Kornbluth. 

MIT Provost Anantha Chandrakasan welcomed the audience, noting that “MITHIC is off to a strong start, advancing work across the Institute that broadens our perspective on global challenges.

“MITHIC is about inspiring our community to think differently and work together in new ways. It is about embedding human-centered thinking throughout our research, innovation, and education,” added Chandrakasan, who serves as co-chair of MITHIC.

Keynote speaker Rick Locke, the John C. Head III Dean of the MIT Sloan School of Management, spoke to the “Human Side of Enterprise,” zeroing in on the challenges and opportunities that will determine the future of management education — and how MIT Sloan can position itself at the forefront. In practice, that means the work of MIT Sloan and MITHIC can shape how new technologies like artificial intelligence will reconfigure industries and careers. 

Of equal importance, Locke said, will be how new enterprises are created and run, how people work and live, how business practices become more sustainable, and how national economies develop and adapt.

“MIT has a history of charting and paving pathways to an exciting and productive future of work that not only includes humans, but makes the most of our humanity. Together we can invent this future,” said Locke, who earned his doctorate in MIT’s Department of Political Science and later served as head of the department.

After his address, Locke joined Agustín Rayo, the Kenan Sahin Dean of the School of Humanities, Arts, and Social Sciences and co-chair of MITHIC, for a fireside chat.

Bringing the classics back to life

In a session exploring innovations in MIT education, Kieran Setiya, the Peter de Florez Professor of Philosophy, detailed what he and his colleagues are calling a “Great Books” initiative. 

As part of a three-year pilot, faculty in the Department of Linguistics and Philosophy have developed a two-semester sequence that focuses on books that reward repeated reading. The courses are loosely integrated and offered as electives, filling what Setiya calls an “urgent need for students to grapple with expansive questions about human nature, human knowledge, ethics, society, and politics” at a time of rapid social and technological change.

As students explore the work of authors like Plato and Aristotle, Homer and Virgil, Virginia Woolf, W.E.B. DuBois, and Simone de Beauvoir, they develop a deeper understanding of history, culture, and social change. These attributes, Setiya says, “will make students better people and better citizens. We're not just preparing MIT students to land high-paying jobs, but to solve human problems and to make the world a better place.”

AI and its impact

During a session on the use of AI, Esther Duflo, the Abdul Latif Jameel Professor of Poverty Alleviation and Development Economics, shared research she is working on in India with co-project lead Marzyeh Ghassemi, associate professor and the Germeshausen Career Development Professor in the Department of Electrical Engineering and Computer Science (EECS). 

Duflo explained that the team is using AI to identify undiagnosed “silent” heart attacks, aiming to improve diagnosis and treatment of heart disease, the country’s No. 1 cause of death. The research team harnessed the power of a cheap diagnostic tool — a handheld electrocardiogram (ECG) device — to collect data on 6,000 patients who visited local health camps to predict their risk of a heart attack. 

They then paired the initial data with follow-up data from a cardiac ultrasound, which was able to confirm if patients experienced one. The researchers used this paired data and their own novel algorithm to train the ECG devices to more accurately assess a patient’s risk. The results are encouraging: 

“What is remarkable compared to existing tests is that it catches young people who are less likely to have had a silent heart attack, but still have a high risk. Right now, those young people are completely excluded from the current screening, because it’s basically based only on age,” Duflo said.

Reconstructing the music of the past

The day also featured a musical demonstration using three different replicas of an ancient Paracas whistle that a team from MIT recreated in collaboration with the Museum of Fine Arts, Boston (MFA).

It was a practical example of how Mark Rau, an assistant professor in music and theater arts with a shared appointment in EECS, and Benjamin Sabatini, a senior postdoc in the Department of Materials Science and Engineering, are using CT scan technology to create models of ancient instruments, measure their vibrations and acoustic parameters, and produce functional reproductions. 

The team offered a step-by-step overview of the process they’ve used to assess the instruments and create the 3D-printed plaster molds, working alongside Jared Katz, the Pappalardo Curator of Musical Instruments at the MFA, resulting in a playable replica of an instrument used centuries ago. 

“What we’re really excited about is getting these kinds of replicas in the hands of students and musicians, and having experimental engagements. We’re also really excited about the printed replicas that allow the collection to be activated in new ways,” Katz explained.

The event featured Q&A opportunities throughout the day, as well as a reception at the close of the day. MITHIC’s second call for proposals this fall yielded nearly 80 submissions, which are under review for funding in 2026. 

A new call for proposals for the SHASS+ Connectivity Fund will be held in spring 2026. SHASS+ supports projects led by a SHASS scholar and a collaborator from another part of the Institute. Another call for proposals for the next FDI seed grant will also take place in spring 2026. 

Waiting in an airport for a connecting flight is often tedious. A new study by MIT researchers shows it’s bad for business, too.

Looking at air travel and multinational firm formation over a 30-year period, the researchers measured how much a strong network of airline connections matters for economic growth. They found that multinational firms are more likely to locate their subsidiaries in cities they can reach with direct flights, and that this trend is particularly pronounced in knowledge industries. The degree to which a city is embedded within a larger network of high-use flights matters notably for business expansion too.

The team examined 142 countries over the period from 1993 through 2023 and concluded that pairs of cities reachable only by flights with one stopover had 20 percent fewer multinational firm subsidiaries than cities with direct flights. If two changes of planes were needed to connect cities, they had 34 percent fewer subsidiaries. That equates to 1.8 percent and 3.0 percent fewer new firms per year, respectively.

“What we found is how much it matters for a city to be embedded within the global air transportation network,” says Ambra Amico, an MIT researcher and co-author of a new paper detailing the study’s results. “And we also highlight the importance of this for knowledge-intensive business sectors.”

Siqi Zheng, an MIT professor and co-author of the paper, adds: “We found a very strong empirical result about the relationship of parent and subsidiary firms, and how much connectivity matters. The important role that connectivity plays to facilitate face-to-face interactions, build trust, and reduce information asymmetry between such firms is crucial.”

The paper, “Air Connectivity Boosts Urban Attractiveness for Global Firms,” is published today in Nature Cities.

The co-authors are Amico, a postdoc at the MIT-Singapore Alliance for Research and Technology (SMART); Fabio Duarte, associate director of MIT’s Senseable City Lab; Wen-Chi Liao, a visiting associate professor at the MIT Center for Real Estate (CRE) and an associate professor at NUS Business School at the National University of Singapore; and Zheng, the STL Champion Professor of Urban and Real Estate Sustainability at CRE and MIT’s Department of Urban Studies and Planning.

The study analyzes 7.5 million firms in 800 cities with airports, comprising a total of over 400,000 international flight routes. The research focused only on multinational firms, and thus international flights, excluding domestic flights in large countries.

To conduct the analysis and build their new database, the researchers used flight data from the International Civil Aviation Organization as well as firm data from the Orbis database, run by Moody’s, which has company data for over 469 million firms globally. That includes ownership data, allowing the researchers to track relationships between companies. The study included firms located within 37 miles (60 kilometers) of an airport, and accounted for additional factors influencing new-firm location, including city size.

By analyzing industry types, the researchers observed that air connectivity matters relatively more in knowledge industries, such as finance, where face-to-face activity seems to matter more. Alternately, a knowledge-industry firm with auditors periodically showing up to conduct work can lower costs by being more reachable.

“We were fascinated by the heterogenity across industries,” Liao says. “The results are intuitive, but it surprised us that the pattern is so consistent. If the nature of the industy requires face-to-face interaction, air connectivity matters more.” By contrast, for manufacturing, he notes, road infrastructure and ocean shipping will matter relatively more.

To be sure, there are multiple ways to define how connected a city is within the global air transportation network, and the study examines how specific measures relate to firm growth. One measure is what the paper calls “degree centrality,” or how many other places a city is connected to by direct flights. Over a 10-year period, a 10 percent increase in a city’s degree centrality leads to a 4.3 percent increase in the number of subsidiaries located there.

However, another kind of connectedness is even more strongly associated with subsidiary growth. It’s not just how many cities one place is linked to, but in turn, how many direct connections those linked cities themselves have. This turns out to be the strongest predictor of subsidiary growth.

“What matters is not just how many neighbor [directly linked] cities you have,” Duarte says. “It’s important to choose strategically which ones you’re connected to, as well. If you tell me who you are connected to, I tell you how successful your city will be.”

Intriguingly, the relationship between direct flights and multinational firm growth patterns has held up throughout the 30-year study period, despite the rise of teleconferencing, the Covid-19 pandemic, shifts in global growth, and other factors.

“There is consistency across a 30-year period, which is not something to underestimate,” Amico says. “We needed face-to-face interaction 30 years ago, 20 years ago, and 10 years ago, and we need it now, despite all the big changes we have seen.”

Indeed, Zheng adds, “Ironically, I think even with trade and geopolitical frictions, it’s more and more important to have face-to-face interactions to build trust for global trade and business. You still need to reach an actual place and see your business partners, so air connectivity really influences how global business copes with global uncertainties.”

The research was supported by the National Research Foundation of Singapore within the Office of the Prime Minister of Singapore, under its Campus for Research Excellence and Technological Enterprise program, and the MIT Asia Real Estate Initiative. 

Can an organization ever be truly meritocratic? That’s a question Emilio J. Castilla, the NTU Professor of Management at the MIT Sloan School of Management, explores in his new book, “The Meritocracy Paradox: Where Talent Management Strategies Go Wrong and How to Fix Them” (Columbia University Press, 2025). Castilla, who is co-director of MIT’s Institute for Work and Employment Research (IWER), researches how talent is managed inside organizations and why — even with the best intentions — workplace practices often fail to deliver fairness and effectiveness.

Castilla’s book brings together decades of research to explain why organizations struggle to achieve meritocracy in practice — and what leaders can do to build fairer, more effective, and higher-performing workplaces. In the following Q&A, he unpacks how bias can unintentionally seep into hiring, evaluation, promotion, and reward systems, and offers concrete strategies to counteract these dynamics and design processes that recognize and support merit.

Q: One central argument of your book is that true meritocracy is not easy for organizations to achieve in practice. Why is that? 

A. A large body of research has found that bias and unfairness can creep into the workplace, affecting talent management processes such as who gets interviewed for jobs, who gets hired, what kind of performance evaluations employees receive, and how employees are rewarded. So it’s not easy for an organization to be truly meritocratic.

In fact, research I conducted with Stephen Benard found that, ironically, emphasizing that an organization is a meritocracy may lead decision-makers to behave in more biased ways. Specifically, in our study, we found that when participants were told they were making decisions for an organization that emphasized meritocracy, they were more likely to recommend higher bonuses for male employees than for their equally-performing female peers, compared to when meritocracy wasn’t emphasized. We called this phenomenon the “paradox of meritocracy,” and it may stem from managers paying less attention to monitoring their own biases when they are assured the organization is fair.

A study I conducted with Aruna Ranganathan PhD ’14 further showed that managers’ understanding of what constitutes “merit” varies widely — even within the same organization. There is no universally agreed-upon definition, and our research found that managers often apply the concept of merit in ways that reflect their own experiences as employees. This variability can lead to inconsistent, and sometimes inequitable, outcomes.

Q. What are some of the things organizations can do to make their talent management practices more meritocratic?

A. The encouraging news is that making your organization’s talent management processes fairer and more meritocratic doesn’t have to be complex or expensive. It does, however, require buy-in from top management. The key factors, my research in organizations has shown, are organizational transparency and accountability.

To improve organizational transparency, you need to be very explicit and open about the criteria and procedures you use in talent management processes such as hiring, evaluation, promotion, and reward decisions. That’s because research has shown that having clear and specific merit-based criteria and well-defined processes can help reduce biases.

On the accountability side, you need to have at least one person responsible for monitoring the organization’s talent management processes and outcomes to ensure fairness and effectiveness. In practice, companies often give this responsibility to a group from different parts of the organization. Research has shown that knowing that your decisions will be reviewed by others causes managers to think carefully about their decisions — something that can reduce the impact of unconscious biases in the workplace.

Q. How realistic is it to think that organizations can ever be true meritocracies — and why do you nonetheless believe meritocracy is worth striving for?

A. It’s true that organizations are unlikely to ever be perfectly meritocratic. Still, striving for meritocracy and fairness in your talent management strategies is beneficial, and you should be aware of the pitfalls. Employers that hire, reward, and advance the most talented and hard-working employees, regardless of their demographic background, are likely to benefit in the long run. That’s the promise and enduring appeal of meritocracy.

Many in the United States may not realize that one of the world’s earliest formal meritocracies emerged in China during the Han and Qin dynasties more than 2,000 years ago. As early as 200 B.C.E., the Chinese empire began developing a system of civil service exams in order to identify and appoint competent and talented officials to help administer government operations throughout the empire.

Those Chinese emperors were on to something. Once an organization reaches a certain size, leaders won’t achieve the most effective performance if they make talent management decisions based on non-meritocratic factors such as nepotism, aristocracy/social class, corruption, or friendship. When it comes to choosing a guiding principle for people management decisions within an organization, meritocracy beats a lot of the alternatives.

Massachusetts is uniquely positioned to become a leader in climate tech, said Emily Reichert MBA ’12, the CEO of the Massachusetts Clean Energy Center (MassCEC) and former CEO of Greentown Labs, to members of the MIT community at a seminar in November. 

Reichert outlined the interconnectedness of economic development and clean energy innovation in MassCEC’s efforts to advance the energy transition and address climate change, as part of the MITEI Presents: Advancing the Energy Transition speaker series. An MIT Sloan School of Management alumna, Reichert stepped aside as the agency’s CEO in late November and the MITEI speaker series was her final presentation in that role.

“There’s not another [agency] in the country exactly like us focused on innovation and economic development for clean energy and climate tech,” stated Reichert. Created in 2008, MassCEC is the state’s economic development agency dedicated to the growth of the clean energy and climate tech sector. Reichert stressed that economic development is just as much about businesses as it is about the jobs they create.

The organization’s economic development plan is built on its knowledge of the commonwealth’s infrastructure, talent capabilities, academic resources, startup culture, and regional strengths. Reichert explained that there are four areas at the core of MassCEC’s work.

First, bringing emerging climate-tech ideas out of the laboratory and into the world. To do this, MassCEC provides grants, internships, and has a small investment fund that is co-invested with different investors in the area. “We are increasingly focusing on the longer-term growth trajectory of these young companies,” said Reichert, adding that the hope is for these startups to stay, grow, and create jobs in Massachusetts.

Second, MassCEC aims to accelerate decarbonization by taking commercialized technologies and helping to get them into as many homes and businesses as possible. This can often require specialized knowledge of Massachusetts’ infrastructure, given that the state has relatively older buildings and unique structures, such as triple-deckers. One example is finding a way to make charging technology available to electric vehicle owners when they don’t have a single-family home with a garage.

MassCEC is also focused on enabling the large-scale deployment of offshore wind. “It’ll be 400,000 homes that are powered by the clean energy that’s being generated by offshore wind right off the coast of Martha’s Vineyard. MassCEC’s role is to support the port infrastructure from which we marshal those offshore wind projects,” stated Reichert. “We also support innovation that is needed to do all the things that support the offshore wind industry, in general.”

Finally, Reichert reiterated that MassCEC’s overarching goal is to support clean energy workforce development through job creation, as well as professional development opportunities such as providing internships, training for high school and community college students, and supporting students returning to school for a second career in clean energy.

Reichert emphasized that Massachusetts is particularly well-equipped to house this level of climate-tech innovation since the state is already a leader in the life sciences. The Healey-Driscoll administration charged MassCEC with spearheading the state’s Climatetech Economic Development Strategy and Implementation Plan, a 10-year strategy to position Massachusetts as a global climate tech leader and drive a more equitable and resilient climate future.

To complement this plan and further position the state as an epicenter for energy innovation, the Healey-Driscoll administration also passed the Mass Leads Act, which established the Climatetech Tax Incentive Program, an annual tax incentive to be administered by MassCEC. “This is the money piece,” said Reichert. “How we do it. How we implement it.”

To unlock Massachusetts’ full potential, MassCEC uses a regional approach to take advantage of the strengths held in each area of the state. “We have a fantastic ecosystem. We have more startups per capita than any other state,” said Reichert. The quantity of startups is in large part due to the strengths of the Greater Boston region, with its strong venture capital community and good research institutions, said Reichert, who also highlighted MIT as a key factor. MIT spinout companies like Sublime Systems, Commonwealth Fusion Systems, Boston Metal, and The Engine are all part of MassCEC’s ecosystem.

For the agency, retaining talent in Massachusetts is just as important as supporting its development. “How can we help companies to do their processes, find their facilities, build their facilities, do their demonstrations, do their testing, and find the talent?” asked Reichert. “How can we reduce the time and money barriers to all of that, and therefore make it as easy as possible and as inexpensive as possible for the company to stay here and grow here?”

Reichert expressed her confidence in climate-tech innovation’s ability to endure the changing energy landscape. “The rest of the world is going in this direction. We can decide not to compete as a country, or we can decide that we want to compete and that we want to be part of the future,” said Reichert. “Innovation isn’t going anywhere. I think when you have places like MIT, who are very focused on climate innovation and the energy transition, that activity helps move the ball forward.”

This speaker series highlights energy experts and leaders at the forefront of the scientific, technological, and policy solutions needed to transform our energy systems. Visit MITEI’s Events page for more information on this and additional events.

Detecting cancer in the earliest stages could dramatically reduce cancer deaths because cancers are usually easier to treat when caught early. To help achieve that goal, MIT and Microsoft researchers are using artificial intelligence to design molecular sensors for early detection.

The researchers developed an AI model to design peptides (short proteins) that are targeted by enzymes called proteases, which are overactive in cancer cells. Nanoparticles coated with these peptides can act as sensors that give off a signal if cancer-linked proteases are present anywhere in the body.

Depending on which proteases are detected, doctors would be able to diagnose the particular type of cancer that is present. These signals could be detected using a simple urine test that could even be done at home.

“We’re focused on ultra-sensitive detection in diseases like the early stages of cancer, when the tumor burden is small, or early on in recurrence after surgery,” says Sangeeta Bhatia, the John and Dorothy Wilson Professor of Health Sciences and Technology and of Electrical Engineering and Computer Science at MIT, and a member of MIT’s Koch Institute for Integrative Cancer Research and the Institute for Medical Engineering and Science (IMES).

Bhatia and Ava Amini ’16, a principal researcher at Microsoft Research and a former graduate student in Bhatia’s lab, are the senior authors of the study, which appears today in Nature Communications. Carmen Martin-Alonso PhD ’23, a founding scientist at Amplifyer Bio, and Sarah Alamdari, a senior applied scientist at Microsoft Research, are the paper’s lead authors.

Amplifying cancer signals

More than a decade ago, Bhatia’s lab came up with the idea of using protease activity as a marker of early cancer. The human genome encodes about 600 proteases, which are enzymes that can cut through other proteins, including structural proteins such as collagen. They are often overactive in cancer cells, as they help the cells escape their original locations by cutting through proteins of the extracellular matrix, which normally holds cells in place.

The researchers’ idea was to coat nanoparticles with peptides that can be cleaved by a specific protease. These particles could then be ingested or inhaled. As they traveled through the body, if they encountered any cancer-linked proteases, the peptides on the particles would be cleaved.

Those peptides would be secreted in the urine, where they could be detected using a paper strip similar to a pregnancy test strip. Measuring those signals would reveal the overactivity of proteases deep within the body.

“We have been advancing the idea that if you can make a sensor out of these proteases and multiplex them, then you could find signatures of where these proteases were active in diseases. And since the peptide cleavage is an enzymatic process, it can really amplify a signal,” Bhatia says.

The researchers have used this approach to demonstrate diagnostic sensors for lung, ovarian, and colon cancers.

However, in those studies, the researchers used a trial-and-error process to identify peptides that would be cleaved by certain proteases. In most cases, the peptides they identified could be cleaved by more than one protease, which meant that the signals that were read could not be attributed to a specific enzyme.

Nonetheless, using “multiplexed” arrays of many different peptides yielded distinctive sensor signatures that were diagnostic in animal models of many different types of cancer, even if the precise identity of the proteases responsible for the cleavage remained unknown.

In their new study, the researchers moved beyond the traditional trial-and-error process by developing a novel AI system, named CleaveNet, to design peptide sequences that could be cleaved efficiently and specifically by target proteases of interest.

Users can prompt CleaveNet with design criteria, and CleaveNet will generate candidate peptides likely to fit those criteria. In this way, CleaveNet enables users to tune the efficiency and specificity of peptides generated by the model, opening a path to improving the sensors’ diagnostic power.

“If we know that a particular protease is really key to a certain cancer, and we can optimize the sensor to be highly sensitive and specific to that protease, then that gives us a great diagnostic signal,” Amini says. “We can leverage the power of computation to try to specifically optimize for these efficiency and selectivity metrics.”

For a peptide that contains 10 amino acids, there are about 10 trillion possible combinations. Using AI to search that immense space allows for prediction, testing, and identification of useful sequences much faster than humans would be able to find them, while also considerably reducing experimental costs.

Predicting enzyme activity

To create CleaveNet, the researchers developed a protein language model to predict the amino acid sequences of peptides, analogous to how large language models can predict sequences of text. For the training data, they used publicly available data on about 20,000 peptides and their interactions with different proteases from a family known as matrix metalloproteinases (MMPs).

Using these data, the researchers trained one model to generate peptide sequences that are predicted to be cleaved by proteases. These sequences could then be fed into another model that predicted how efficiently each peptide would be cleaved by any protease of interest.

To demonstrate this approach, the researchers focused on a protease called MMP13, which cancer cells use to cut through collagen and help them metastasize from their original locations. Prompting CleaveNet with MMP13 as a target allowed the models to design peptides that could be cut by MMP13 with considerable selectivity and efficiency. This cleavage profile is particularly useful for diagnostic and therapeutic applications.

“When we set the model up to generate sequences that would be efficient and selective for MMP13, it actually came up with peptides that had never been observed in training, and yet these novel sequences did turn out to be both efficient and selective,” Martin-Alonso says. “That was very exciting to see.”

This kind of selectivity could help to reduce the number of different peptides needed to diagnose a given type of cancer, to identify novel biomarkers, and to provide insight into specific biological pathways for study and therapeutic testing, the researchers say.

Bhatia’s lab is currently part of an ARPA-H funded project to create reporters for an at-home diagnostic kit that could potentially detect and distinguish between 30 different types of cancer, in early stages of disease, based on measurements of protease activity. These sensors could include detection of not only MMP-mediated cleavage, but other enzymes such as serine proteases and cysteine proteases.

Peptides designed using CleaveNet could also be incorporated into cancer therapeutics such as antibody treatments. Using a specific peptide to attach a therapeutic such as a cytokine or small molecule drug to a targeting antibody could enable the medicine to be released only when the peptides are exposed to proteases in the tumor environment, improving efficacy and reducing side effects.

Beyond direct applications in diagnostics and therapeutics, combining efforts from the ARPA-H work with this modeling framework could enable the creation of a comprehensive “protease activity atlas” that spans multiple protease classes and cancers. Such a resource could further accelerate research in early cancer detection, protease biology, and AI models for peptide design.

The research was funded by La Caixa Foundation, the Ludwig Center at MIT, and the Marble Center for Cancer Nanomedicine.

In elementary school, Sean Luk loved donning an oversized lab coat and helping her mom pipette chemicals at Johns Hopkins University. A few years later, she started a science blog and became fascinated by immunoengineering, which is now her concentration as a biological engineering major at MIT.

Her grandparents’ battles with cancer made Luk, now a senior, realize how urgently patients need advancements in immunotherapy, which leverages a patient’s immune system to fight tumors or pathogens.

“The idea of creating something that is actually able to improve human health is what really drives me now. You want to fight that sense of helplessness when you see a loved one suffering through this disease, and it just further motivates me to be excellent at what I do,” Luk says.

A varsity athlete and entrepreneur as well as a researcher, Luk thrives when bringing people together for a common cause.

Working with immunotherapies

Luk was introduced to immunotherapies in high school after she listened to a seminar about using components of the immune system, such as antibodies and cytokines, to improve graft tolerance.

“The complexity of the immune system really fascinated me, and it is incredible that we can build antibodies in a very logical way to address disease,” Luk says.

She worked in several Johns Hopkins labs as a high school student in Maryland, and a professor there connected her to MIT Professor Dane Wittrup. Luk has worked in the Wittrup lab throughout her time at MIT. One of her main projects involves developing ultra-stable cyclic peptide drugs to help treat autoimmune diseases, which could potentially be taken orally instead of injected.

Luk has been a co-author on two published articles and has become increasingly interested in the intersection between computational and experimental protein design. Currently, she is working on engineering an interferon gamma construct that preferentially targets myeloid cells in the tumor microenvironment.

“We're trying to target and reprogram the immunosuppressive myeloid cells surrounding the cancer cells, so that they can license T cells to attack cancer cells and kickstart the cancer immunity cycle,” she explains.

Communication for all

Through her work in high school with Best Buddies, an organization that aims to promote one-on-one friendships between students with and without intellectual and developmental disabilities, Luk became passionate about empowering people with special needs. At MIT, she started a project focusing on children with Down syndrome, with support from the Sandbox Innovation Fund.

“Through talking to a lot of parents and caretakers, the biggest issue that people with Down syndrome face is communication. And when you think about it, communication is crucial to everything that we do,” Luk says, “We want to communicate our thoughts. We want to be able to interact with our peers. And if people are unable to do that, it’s isolating, it’s frustrating.”

Her solution was to co-found EasyComm, an online game platform that helps children with Down syndrome work on verbal communication.

“We thought it would be a great way to improve their verbal communication skills while having fun and incentivize that kind of learning through gamification,” Luk says. She and her co-founder recently filed a provisional patent and plan to make the platform available to a wider audience.

A global perspective

Luk grew up in Hong Kong before moving to Maryland in the fifth grade. She’s always been athletic; in Hong Kong, she was a competitive jump roper. At just 9 years old, she won bronze in the Asian Jump Rope Championships among children 14 years old and younger. At 7 years old, she started playing soccer on her brother’s team, despite being the only girl. She says the sport was considered “manly” in Hong Kong, and girls were discouraged from joining, but her coaches and family were supportive.

Moving to the U.S. meant that her time in competitive jump roping was cut short, and Luk focused more on soccer. Her team in the U.S. felt far more intense than boys soccer in Hong Kong, but the Luk family was in it together, Luk says. She credits her success to the combination of her hard-working nature she learned from Hong Kong, and the innovation and experiences she was exposed to in the U.S.

“We had a really close bond within the family,” Luk says, “Figuring out taxes for my dad and our family, like driving and houses and all that stuff, it was totally new. But I think we really took it in stride, just adjusting as we went.”

Luk continued soccer throughout high school and eventually committed to play on the MIT team. She likes that the team allows players to prioritize academics while still being competitive. Last season, she was elected captain.

“It’s really a pleasure to be captain, and it’s challenging, but it’s also very rewarding when you see the team be cohesive. When you see the team out there winning games through grit,” Luk says.

During her first year at MIT, Luk got back in touch with her old soccer coach from Hong Kong, who then worked on the national team. After sending over some tape, she was offered a spot on the U-20 national team, and played in the U20 Asian Football Championship Qualifiers.

“It was so, so cool to be able to represent Hong Kong because I played soccer all my life but it just carries a different weight to it when you’re wearing your country’s jersey,” Luk says.

Besides her cross-cultural background, Luk is also proud of her international experiences playing soccer, staying with host families and doing lab work in Copenhagen, Denmark; Stuttgart, Germany; and Ancona, Italy. She speaks English, Cantonese, and Mandarin fluently.

“Aside from the textbook academic knowledge, I feel like a global perspective is so important when you’re trying to collaborate with other people from different walks of life,” Luk says, “When you’re just thinking about science or the impact that you can have in general, it’s important to realize you don’t have all the answers and to learn from the world outside your little bubble.”

What is patient privacy for? The Hippocratic Oath, thought to be one of the earliest and most widely known medical ethics texts in the world, reads: “Whatever I see or hear in the lives of my patients, whether in connection with my professional practice or not, which ought not to be spoken of outside, I will keep secret, as considering all such things to be private.” 

As privacy becomes increasingly scarce in the age of data-hungry algorithms and cyberattacks, medicine is one of the few remaining domains where confidentiality remains central to practice, enabling patients to trust their physicians with sensitive information.

But a paper co-authored by MIT researchers investigates how artificial intelligence models trained on de-identified electronic health records (EHRs) can memorize patient-specific information. The work, which was recently presented at the 2025 Conference on Neural Information Processing Systems (NeurIPS), recommends a rigorous testing setup to ensure targeted prompts cannot reveal information, emphasizing that leakage must be evaluated in a health care context to determine whether it meaningfully compromises patient privacy.

Foundation models trained on EHRs should normally generalize knowledge to make better predictions, drawing upon many patient records. But in “memorization,” the model draws upon a singular patient record to deliver its output, potentially violating patient privacy. Notably, foundation models are already known to be prone to data leakage.

“Knowledge in these high-capacity models can be a resource for many communities, but adversarial attackers can prompt a model to extract information on training data,” says Sana Tonekaboni, a postdoc at the Eric and Wendy Schmidt Center at the Broad Institute of MIT and Harvard and first author of the paper. Given the risk that foundation models could also memorize private data, she notes, “this work is a step towards ensuring there are practical evaluation steps our community can take before releasing models.”

To conduct research on the potential risk EHR foundation models could pose in medicine, Tonekaboni approached MIT Associate Professor Marzyeh Ghassemi, who is a principal investigator at the Abdul Latif Jameel Clinic for Machine Learning in Health (Jameel Clinic) and a member of the Computer Science and Artificial Intelligence Lab. Ghassemi, a faculty member in the MIT Department of Electrical Engineering and Computer Science and Institute for Medical Engineering and Science, runs the Healthy ML group, which focuses on robust machine learning in health.

Just how much information does a bad actor need to expose sensitive data, and what are the risks associated with the leaked information? To assess this, the research team developed a series of tests that they hope will lay the groundwork for future privacy evaluations. These tests are designed to measure various types of uncertainty, and assess their practical risk to patients by measuring various tiers of attack possibility.  

“We really tried to emphasize practicality here; if an attacker has to know the date and value of a dozen laboratory tests from your record in order to extract information, there is very little risk of harm. If I already have access to that level of protected source data, why would I need to attack a large foundation model for more?” says Ghassemi. 

With the inevitable digitization of medical records, data breaches have become more commonplace. In the past 24 months, the U.S. Department of Health and Human Services has recorded 747 data breaches of health information affecting more than 500 individuals, with the majority categorized as hacking/IT incidents.

Patients with unique conditions are especially vulnerable, given how easy it is to pick them out. “Even with de-identified data, it depends on what sort of information you leak about the individual,” Tonekaboni says. “Once you identify them, you know a lot more.”

In their structured tests, the researchers found that the more information the attacker has about a particular patient, the more likely the model is to leak information. They demonstrated how to distinguish model generalization cases from patient-level memorization, to properly assess privacy risk. 

The paper also emphasized that some leaks are more harmful than others. For instance, a model revealing a patient’s age or demographics could be characterized as a more benign leakage than the model revealing more sensitive information, like an HIV diagnosis or alcohol abuse. 

The researchers note that patients with unique conditions are especially vulnerable given how easy it is to pick them out, which may require higher levels of protection. “Even with de-identified data, it really depends on what sort of information you leak about the individual,” Tonekaboni says. The researchers plan to expand the work to become more interdisciplinary, adding clinicians and privacy experts as well as legal experts. 

“There’s a reason our health data is private,” Tonekaboni says. “There’s no reason for others to know about it.”

This work supported by the Eric and Wendy Schmidt Center at the Broad Institute of MIT and Harvard, Wallenberg AI, the Knut and Alice Wallenberg Foundation, the U.S. National Science Foundation (NSF), a Gordon and Betty Moore Foundation award, a Google Research Scholar award, and the AI2050 Program at Schmidt Sciences. Resources used in preparing this research were provided, in part, by the Province of Ontario, the Government of Canada through CIFAR, and companies sponsoring the Vector Institute.

A long stretch of humid heat followed by intense thunderstorms is a weather pattern historically seen mostly in and around the tropics. But climate change is making humid heat waves and extreme storms more common in traditionally temperate midlatitude regions such as the midwestern U.S., which has seen episodes of unusually high heat and humidity in recent summers.

Now, MIT scientists have identified a key condition in the atmosphere that determines how hot and humid a midlatitude region can get, and how intense related storms can become. The results may help climate scientists gauge a region’s risk for humid heat waves and extreme storms as the world continues to warm.

In a study appearing this week in the journal Science Advances, the MIT team reports that a region’s maximum humid heat and storm intensity are limited by the strength of an “atmospheric inversion”— a weather condition in which a layer of warm air settles over cooler air.

Inversions are known to act as an atmospheric blanket that traps pollutants at ground level. Now, the MIT researchers have found atmospheric inversions also trap and build up heat and moisture at the surface, particularly in midlatitude regions. The more persistent an inversion, the more heat and humidity a region can accumulate at the surface, which can lead to more oppressive, longer-lasting humid heat waves.

And, when an inversion eventually weakens, the accumulated heat energy is released as convection, which can whip up the hot and humid air into intense thunderstorms and heavy rainfall.

The team says this effect is especially relevant for midlatitude regions, where atmospheric inversions are common. In the U.S., regions to the east of the Rocky Mountains often experience inversions of this kind, with relatively warm air aloft sitting over cooler air near the surface.

As climate change further warms the atmosphere in general, the team suspects that inversions may become more persistent and harder to break. This could mean more frequent humid heat waves and more intense storms for places that are not accustomed to such extreme weather.

“Our analysis shows that the eastern and midwestern regions of U.S. and the eastern Asian regions may be new hotspots for humid heat in the future climate,” says study author Funing Li, a postdoc in MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS).

“As the climate warms, theoretically the atmosphere will be able to hold more moisture,” adds co-author and EAPS Assistant Professor Talia Tamarin-Brodsky. “Which is why new regions in the midlatitudes could experience moist heat waves that will cause stress that they weren’t used to before.”

Air energetics

The atmosphere’s layers generally get colder with altitude. In these typical conditions, when a heat wave comes through a region, it warms the air at ground level. Since warm air is lighter than cold air, it will eventually rise, like a hot air balloon, prompting colder air to sink. This rise and fall of air sets off convection, like bubbles in boiling water. When warm air hits colder altitudes, it condenses into droplets that rain out, typically as a thunderstorm, that can often relieve a heat wave.

For their new study, Li and Tamarin-Brodsky wondered: What would it take to get air at the surface to convect and ultimately end a heat wave? Put another way: What sets the limit to how hot a region can get before air begins to convect to eventually rain?

The team treated the question as a problem of energy. Heat is energy that can be thought of in two forms: the energy that comes from dry heat (i.e., temperature), and the energy that comes from latent, or moist, heat. The scientists reasoned that, for a given portion or “parcel” of air, there is some amount of moisture that, when condensed, contributes to that air parcel’s total energy. Depending on how much energy an air parcel has, it could start to convect, rise up, and eventually rain out.

“Imagine putting a balloon around a parcel of air and asking, will it stay in the same place, will it go up, or will it sink?” Tamarin-Brodsky says. “It’s not just about warm air that’s lifting. You also have to think about the moisture that’s there. So we consider the energetics of an air parcel while taking into account the moisture in that air. Then we can find the maximum ‘moist energy’ that can accumulate near the surface before the air becomes unstable and convects.”

Heat barrier

As they worked through their analysis, the researchers found that the maximum amount of moist energy, or the highest level of heat and humidity that the air can hold, is set by the presence and strength of an atmospheric inversion. In cases where atmospheric layers are inverted (when a layer of warm or light air settles over colder or heavier, ground-level air), the air has to accumulate more heat and moisture in order for an air parcel to build up enough energy to lift up and break through the inversion layer. The more persistent the inversion is, the hotter and more humid air must get before it can rise up and convect.

Their analysis suggests that an atmospheric inversion can increase a region’s capacity to hold heat and humidity. How high this heat and humidity can get depends on how stable the inversion is. If a blanket of warm air parks over a region without moving, it allows more humid heat to build up, versus if the blanket is quickly removed. When the air eventually convects, the accumulated heat and moisture will generate stronger, more intense storms.

“This increasing inversion has two effects: more severe humid heat waves, and less frequent but more extreme convective storms,” Tamarin-Brodsky says.

Inversions in the atmosphere form in various ways. At night, the surface that warmed during the day cools by radiating heat to space, making the air in contact with it cooler and denser than the air above. This creates a shallow layer in which temperature increases with height, called a nocturnal inversion. Inversions can also form when a shallow layer of cool marine air moves inland from the ocean and slides beneath warmer air over the land, leaving cool air near the surface and warmer air above. In some cases, persistent inversions can form when air heated over sun-warmed mountains is carried over colder low-lying regions, so that a warm layer aloft caps cooler air near the ground.

“The Great Plains and the Midwest have had many inversions historically due to the Rocky Mountains,” Li says. “The mountains act as an efficient elevated heat source, and westerly winds carry this relatively warm air downstream into the central and midwestern U.S., where it can help create a persistent temperature inversion that caps colder air near the surface.”

“In a future climate for the Midwest, they may experience both more severe thunderstorms and more extreme humid heat waves,” Tamarin-Brodsky says. “Our theory gives an understanding of the limit for humid heat and severe convection for these communities that will be future heat wave and thunderstorm hotspots.”

This research is part of the MIT Climate Grand Challenge on Weather and Climate Extremes. Support was provided by Schmidt Sciences.

MIT researchers have developed a new method for designing 3D structures that can be transformed from a flat configuration into their curved, fully formed shape with only a single pull of a string.

This technique could enable the rapid deployment of a temporary field hospital at the site of a disaster such as a devastating tsunami — a situation where quick medical action is essential to save lives.

The researchers’ approach converts a user-specified 3D structure into a flat shape composed of interconnected tiles. The algorithm uses a two-step method to find the path with minimal friction for a string that can be tightened to smoothly actuate the structure.

The actuation mechanism is easily reversible, and if the string is released, the structure quickly returns to its flat configuration. This could enable complex, 3D structures to be stored and transported more efficiently and with less cost.

In addition, the designs generated by their system are agnostic to the fabrication method, so complete structures can be produced using 3D printing, CNC milling, molding, or other techniques.

This method could enable the creation of transportable medical devices, foldable robots that can flatten to enter hard-to-reach spaces, or even modular space habitats that can be actuated by robots working on the surface of Mars.

“The simplicity of the whole actuation mechanism is a real benefit of our approach. The user just needs to provide their intended design, and then our method optimizes it in such a way that it holds the shape after just one pull on the string, so the structure can be deployed very easily. I hope people will be able to use this method to create a wide variety of different, deployable structures,” says Akib Zaman, an electrical engineering and computer science (EECS) graduate student and lead author of a paper on this new method.

He is joined on the paper by MIT graduate student Jacqueline Aslarus; postdoc Jiaji Li; Associate Professor Stefanie Mueller, leader of the Human-Computer Interaction (HCI) Engineering Group in the Computer Science and Artificial Intelligence Laboratory (CSAIL); and senior author Mina Konaković Luković, an assistant professor and leader of the Algorithmic Design Group in CSAIL. The research was presented at the Association for Computing Machinery’s SIGGRAPH Conference and Exhibition on Computer Graphics and Interactive Techniques in Asia.

From ancient art to an algorithm

Creating deployable structures from flat pieces simplifies on-site assembly and could be especially useful in constructing emergency shelters after natural disasters. On a smaller scale, items like foldable bike helmets could improve the safety of riders who would otherwise be unable to carry a bulky helmet.

But converting flat, deployable objects into their 3D shape often requires specialized equipment or multiple steps, and the actuation mechanism is typically difficult to reverse.

“Because of these challenges, deployable structures tend to be manually designed and quite simple, geometrically. But if we can create more complex geometries, while simplifying the actuation mechanism, we could enhance the capabilities of these deployables,” Zaman says.

To do this, the researchers created a method that automatically converts a user’s 3D design into a flat structure comprised of tiles, connected by rotating hinges at the corners, which can be fully actuated by pulling a single string one time.

Their method breaks a user design into a grid of quadrilateral tiles inspired by kirigami, the ancient Japanese art of paper cutting. With kirigami, by cutting a material in certain ways, they can encode it with unique properties. In this case, they use kirigami to create an auxetic mechanism, which is a structure that gets thicker when stretched and thinner when compressed.

After encoding the 3D geometry into a flat set of auxetic tiles, the algorithm computes the minimum number of points that the tightening string must lift to fully deploy the 3D structure. Then, it finds the shortest path that connects those lift points, while including all areas of the object’s boundary that must be connected to guide the structure into its 3D configuration. It does these calculations in such a way that the optimal string path minimizes friction, enabling the structure to be smoothly actuated with just one pull.

“Our method makes it easy for the user. All they have to do is input their design, and our algorithm automatically takes care of the rest. Then all the user needs to do is to fabricate the tiles exactly the way it has been computed by the algorithm,” Zaman says.

For instance, one could fabricate a structure using a multi-material 3D printer that prints the hinges of the tiles with a flexible material and the other surfaces with a hard material.

A scale independent method

One of the biggest challenges the researchers faced was figuring out how the string route and the friction within the string channel can be effectively modeled as close to physical reality.

“While playing with a few fabricated models, we observed that closing boundary tiles is a must to enable a successful deployment and the string must be routed through them. Later, we proved this observation mathematically. Then, we looked back at an age-old physics equation and used it to formulate the optimization problem for friction minimization,” he says.

They built their automatic algorithm into an interactive user interface that allows one to design and optimize configurations to generate manufacturable objects.

The researchers used their method to design several objects of different sizes, from personalized medical items including a splint and a posture corrector to an igloo-like portable structure. They also fabricated a deployable, human-scale chair they designed using their method.

This method is scale independent, so it could be used to create tiny deployable objects that are injected and actuated inside the body, or architectural structures, like the frame of a building, that are deployed and actuated on-site using cranes.

In the future, the researchers want to further explore the design of tiny structures, while also tackling the engineering challenges involved in creating architectural installations, such as determining the ideal cable thickness and the necessary strength of the hinges. In addition, they want to create a self-deploying mechanism, so the structures do not need to be actuated by a human or robot.

This research is funded, in part, by an MIT Research Support Committee Award.

“At MIT, innovation ranges from awe-inspiring technology to down-to-Earth creativity,” noted Chronicle, during a campus visit this year for an episode of the program. In 2025, MIT researchers made headlines across print publications, podcasts, and video platforms for key scientific advances, from breakthroughs in quantum and artificial intelligence to new efforts aimed at improving pediatric health care and cancer diagnosis.

MIT faculty, researchers, students, alumni and staff helped demystify new technologies, highlighted the practical hands-on learning the Institute is known for, and shared what inspires their research with viewers, readers and listeners around the world. Below is a sampling of news moments to revisit.

Let’s take a closer look at MIT: It’s alarming to see such a complex, important institution subject to the whims of today’s politics
Washington Post columnist George F. Will reflects on MIT and his view of “the damage that can be done to America’s meritocracy by policies motivated by hostility toward institutions vital to it.” Will notes that MIT has an “astonishing economic multiplier effect: MIT graduates have founded companies that have generated almost $1.9 trillion in annual revenue (a sum almost equal to Russia’s GDP) and 4.6 million jobs.”
Full story via The Washington Post

At MIT, groundbreaking ideas blend science and breast cancer detection innovation
Chronicle visited MIT this spring to learn more about how the Institute “nurtures groundbreaking efforts, reminding us that creativity and science thrive together, inspiring future advancements in engineering, medicine, and beyond.”
Full story via Chronicle

New MIT provost looks to build more bridges with CEOs
Provost Anantha Chandrakasan shares his energy and enthusiasm for MIT, and his goals for the Institute.
Full story via The Boston Globe

Five things New England researchers helped develop with federal funding
Professors John Guttag and David Mindell discuss MIT’s long history of developing foundational technologies — including the internet and the first widely used electronic navigation system — with the support of federal funding.
Full story via The Boston Globe

Bostonians of the Year 2025: First responders, university presidents, and others who exemplified courage
President Sally Kornbluth is honored by The Boston Globe as one of the Bostonians of the Year, a list that spotlights individuals across the region who, in choosing the difficult path, “showed us what strength looks like.” Kornbluth was recognized for her work being of the “most prominent voices rallying to protect academic freedom.”
Full story via The Boston Globe

Practical education and workforce preparation

College students flock to a new major: AI
MIT’s new Artificial Intelligence and Decision Making major is aimed at teaching students to “develop AI systems and study how technologies like robots interact with humans and the environment.”
Full story via New York Times

50 colleges with the best ROI
MIT has been named among the top colleges in the country for return on investment. MIT “is need-blind and full-need for undergraduate students. Six out of 10 students receive financial aid, and almost 88% of the Class of 2025 graduated debt-free.”
Full story via Boston 25

Desirée Plata: Chemist, oceanographer, engineer, entrepreneur
Professor Desirée Plata explains that she is most proud of her work as an educator. “The faculty of the world are training the next generation of researchers,” says Plata. “We need a trained workforce. We need patient chemists who want to solve important problems.”
Full story via Chemical & Engineering News

Taking a quantum leap

MIT launches quantum initiative to tackle challenges in science, health care, national security
MIT is “taking a quantum leap with the launch of the new MIT Quantum Initiative (QMIT). “There isn't a more important technological field right now than quantum with its enormous potential for impact on both fundamental research and practical problems,” said President Sally Kornbluth.
Full story via State House News Service

Peter Shor on how quantum tech can help climate
Professor Peter Shor helps disentangle quantum technologies.
Full story via The Quantum Kid

MIT researchers develop device to enable direct communication between multiple quantum processors
MIT researchers made a key advance in the creation of a practical quantum computer.
Full story via Military & Aerospace Electronics

Fortifying national security and aiding disaster response

Nano-material breakthrough could revolutionize night vision
MIT researchers developed “a new way to make large ultrathin infrared sensors that don’t need cryogenic cooling and could radically change night vision for the military.”
Full story via Defense One

MIT researchers develop robot designed to help first-responders in disaster situations
Researchers at MIT engineered SPROUT (Soft Pathfinding Robotic Observation Unit), a robot aimed at assisting first-responders.
Full story via WHDH

MIT scientists make “smart” clothes that warn you when you’re sick
As part of an effort to help keep service members safe, MIT scientists created a programmable fiber that can be stitched into clothing to help monitor the wearer’s health.
Full story via FOX 28

MIT Lincoln Lab develops ocean-mapping technology
MIT Lincoln Laboratory researchers are developing “automated electric vessels to map the ocean floor and improve search and rescue missions.”
Full story via Chronicle

Transformative tech

This MIT scientist is rewiring robots to keep the humanity in tech
Professor Daniela Rus, director of the Computer Science and Artificial Intelligence Lab, discusses her work revolutionizing the field of robotics by bringing “empathy into engineering and proving that responsibility is as radical and as commercially attractive as unguarded innovation.”
Full story via Forbes

Watch this tiny robot somersault through the air like an insect
Professor Kevin Chen designed a tiny, insect-sized aerial microrobot.
Full story via Science

It's actually really hard to make a robot, guys
Professor Pulkit Agrawal delves into his work engineering a simulator that can be used to train robots.
Full story via NPR

Shape-shifting fabrics and programmable materials redefine design at MIT
Associate Professor Skylar Tibbits is embedding intelligence into the materials around us, while Professor Caitlin Mueller and Sandy Curth PhD ’25 are digging into eco-friendly construction.
Full story via Chronicle

Building a healthier future

MIT launches pediatric research hub to address access gaps
The Hood Pediatric Innovation Hub is addressing “underinvestment in pediatric healthcare innovations.”
Full story via Boston Business Journal

Bionic knee helps amputees walk naturally again
Professor Hugh Herr developed a prosthetic that could increase mobility for above-the-knee amputees. “The bionic knee developed by MIT doesn’t just restore function, it redefines it.”
Full story via Fox News

MIT drug hunters are using AI to design completely new antibiotics
Professor James Collins is using AI to develop new compounds to combat antibiotic resistance.
Full story via Fast Company

Innovative once-weekly capsule helps quell schizophrenia symptoms
A new pill from the lab of Associate Professor Giovanni Traverso “can greatly simplify the drug schedule faced by schizophrenia patients.”
Full story via Newsmax

Renewing American manufacturing

US manufacturing is in “pretty bad shape.” MIT hopes to change that.
MIT launched the Initiative for New Manufacturing to help “build the tools and talent to shape a more productive and sustainable future for manufacturing.”
Full story via Manufacturing Dive

Giving US manufacturing a boost
Ben Armstrong of the MIT Industrial Performance Center discusses how to reinvigorate manufacturing in America.
Full story via Marketplace

New England companies are sparking an industrial revolution. Here’s how to harness it.
Professor David Mindell spotlights how “a new wave of industrial companies, many in New England, are leveraging new technologies to create jobs and empower workers.”
Full story via The Boston Globe 

Improving aging

My day as an 80-year-old. What an age-simulation suit taught me.
To get a better sense of the experience of aging, Wall Street Journal reporter Amy Dockser Marcus donned the MIT AgeLab’s age-simulation suit and embarked on multiple activities.
Full story via The Wall Street Journal

New mobile robot helps seniors walk safely and prevent falls
A mobile robot created by MIT engineers is designed to help prevent falls. “It's easy to see how something like this could make a big difference for seniors wanting to stay independent.”
Full story via Fox News

The senior population is booming. Caregiving is struggling to keep up
Professor Jonathan Gruber discusses the labor shortages impacting senior care.
Full story via CNBC

Upping our energy resilience

New MIT collaboration with GE Vernova aims to accelerate energy transition
“A great amount of innovation happens in academia. We have a longer view into the future,” says Provost Anantha Chandrakasan of the MIT-GE Vernova Energy and Climate Alliance.
Full story via The Boston Globe

The environmental impacts of generative AI
Noman Bashir, a fellow with MIT’s Climate and Sustainability Consortium, explores the environmental impacts of generative AI.
Full story via Fox 13

Is the clean energy economy doomed?
Professor Christopher Knittel discusses how the U.S. can be in the best position for global energy dominance.
Full story via Marketplace

Advancing American workers

WTH can we do to prevent a second China shock? Professor David Autor explains
Professor David Autor shares his research examining the long-term impact of China entering the World Trade Organization, how the U.S. can protect vital industries from unfair trade practices, and the potential impacts of AI on workers.
Full story via American Enterprise Institute

The fight over robots threatening American jobs
Professor Daron Acemoglu highlights the economic and societal implications of integrating automation in the workforce, advocating for policies aimed at assisting workers.
Full story via Financial Times

Moving toward automation
Research Scientist Eva Ponce of the MIT Center for Transportation and Logistics notes that robotics and AI technologies are “replacing some jobs — particularly more manual tasks including heavy lifting — but have also offered new opportunities within warehouse operations.”
Full story via Financial Times

Planetary defense and out-of-this world exploration

MIT researchers create new asteroid detection methods to help protect Earth
Associate Professor Julien de Wit and Research Scientist Artem Burdanov discuss their work developing a new method to track asteroids that could impact Earth.
Full story via WBZ Radio

What happens to the bodies of NASA astronauts returning to Earth?
Professor Dava Newman speaks about how long-duration stays in space can affect the human body.
Full story via News Nation

Lunar lander Athena is packed and ready to explore the moon. Here’s what on board
MIT engineers sent three payloads into space on a course set for the moon’s south polar region.
Full story via USA Today

Scanning the heavens at the Vatican Observatory
Br. Guy Consolmagno '74, SM '75, director of the Vatican Observatory, and graduate student Isabella Macias share their experiences studying astronomy and planetary formation at the Vatican Observatory. “The Vatican has such a deep, rich history of working with astronomers,” says Macias. “It shows that science is not only for global superpowers around the world, but it's for students, it's for humanity.”
Full story via CBS News Sunday Morning

The story of real-life rocket scientists
Professor Kerri Cahoy takes viewers on an out-of-this-world journey into how a college internship inspired her research on space and satellites.
Full story via Bloomberg Television 

On the air 

While digital currency initiatives expand, we ask: What’s the future of cash?
Neha Narula, director of the MIT Digital Currency Initiative, examines the future of cash as the use of digital currencies expands.
Full story via USA Today

The high stakes of the AI economy
Professor Asu Ozdaglar, head of the Department of Electrical Engineering and Computer Science and deputy dean of the MIT Schwarzman College of Computing, explores AI’s opportunities and risks — and whether it can be regulated without stifling progress.
Full story via Is Business Broken? 

The LIGO Lab is pushing the boundaries of gravitational-wave research
Associate Professor Matt Evans explores the future of gravitational wave research and how Cosmic Explorer, the next-generation gravitational wave observatory, will help unearth secrets of the early universe.
Full story via Scientific American

Space junk: The impact of global warming on satellites
Graduate student Will Parker discusses his research examining the impact of climate change on satellites.
Full story via USA Today

Endometriosis is common. Why is getting diagnosed so hard?
Professor Linda Griffith shares her work studying endometriosis and her efforts to improve healthcare for women.
Full story via Science Friday

There’s nothing small about this nanoscale research
Professor Vladimir Bulović takes listeners on a tour of MIT.nano, MIT’s “clean laboratory facility that is critical to nanoscale research, from microelectronics to medical nanotechnology.”
Full story via Scientific American

Marrying science and athletics

The MIT scientist behind the “torpedo bats” that are blowing up baseball
Aaron Leanhardt PhD ’03 went from an MIT graduate student who was part of a research team that “cooled sodium gas to the lowest temperature ever recorded in human history” to inventor of the torpedo baseball bat, “perhaps the most significant development in bat technology in decades.”
Full story via The Wall Street Journal

Engineering athletes redefine routine
After suffering a concussion during her sophomore year, Emiko Pope ’25 was inspired to explore the effectiveness of concussion headbands.
Full story via American Society of Mechanical Engineers

“I missed talking math with people”: why John Urschel left the NFL for MIT
Assistant Professor John Urschel shares his decision to call an audible and leave his NFL career to focus on his love for math at MIT.
Full story via The Guardian

Making a statement, MIT’s football team dons extra head padding for safety
It’s a piece of equipment that may become more widely used as research continues into its effectiveness — including from at least one of the players on the current team.
Full story via GBH Morning Edition

Agricultural efficiency

New MIT breakthrough could save farmers billions on pesticides
MIT engineers developed a system that helps pesticides adhere more effectively to plant leaves, allowing farmers to use fewer chemicals.
Full story via Michigan Farm News

Bug-sized robots could help pollination on future farms
Insect-sized robots crafted by MIT researchers could one day be used to help with farming practices like artificial pollination.
Full story via Reuters

See how MIT researchers harvest water from the air
An ultrasonic device created by MIT engineers can extract clean drinking water from atmospheric moisture.
Full story via CNN

Appreciating art

Meet the engineer using deep learning to restore Renaissance art
Graduate student Alex Kachkine talks about his work applying AI to develop a restoration method for damaged artwork.
Full story via Nature

MIT’s Linde Music Building opens with a free festival
“The extent of art-making on the MIT campus is equal to that of a major city,” says Institute Professor Marcus Thompson. “It’s a miracle that it’s all right here, by people in science and technology who are absorbed in creating a new world and who also value the past, present and future of music and the arts.”
Full story via Cambridge Day

“Remembering the Future” on display at the MIT Museum
The “Remembering the Future” exhibit at the MIT Museum features a sculptural installation that uses “climate data from the last ice age to the present, as well as projected future environments, to create a geometric design.”
Full story via The New York Times 

In 2025, MIT maintained its standard of community and research excellence amidst a shift in national priorities regarding the federal funding of higher education. Notably, QS ranked MIT No. 1 in the world for the 14th straight year, while U.S. News ranked MIT No. 2 in the nation for the 5th straight year.

This year, President Sally Kornbluth also added to the Institute’s slate of community-wide strategic initiatives, with new collaborative efforts focused on manufacturing, generative artificial intelligence, and quantum science and engineering. In addition, MIT opened several new buildings and spaces, hosted a campuswide art festival, and continued its tradition of bringing the latest in science and technology to the local community and to the world. Here are some of the top stories from around MIT over the past 12 months.

MIT collaboratives

President Kornbluth announced three new Institute-wide collaborative efforts designed to foster and support alliances that will take on global problems. The Initiative for New Manufacturing (INM) will work toward bolstering industry and creating jobs by driving innovation across vital manufacturing sectors. The MIT Generative AI Impact Consortium (MGAIC), a group of industry leaders and MIT researchers, aims to harness the power of generative artificial intelligence for the good of society. And the MIT Quantum Initiative (QMIT) will leverage quantum breakthroughs to drive the future of scientific and technological progress.

These missions join three announced last year — the Climate Project at MIT, the MIT Human Insight Collaborative (MITHIC), and the MIT Health and Life Sciences Collaborative (MIT HEALS).

Sharing the wonders of science and technology

This year saw the launch of MIT Learn, a dynamic AI-enabled website that hosts nearly 13,000 non-degree learning opportunities, making it easier for learners around the world to discover the courses and resources available on MIT’s various learning platforms.

The Institute also hosted the Cambridge Science Carnival, a hands-on event managed by the MIT Museum that drew approximately 20,000 attendees and featured more than 140 activities, demonstrations, and installations tied to the topics of science, technology, engineering, arts, and mathematics (STEAM).

Commencement

At Commencement, Hank Green urged MIT’s newest graduates to focus their work on the “everyday solvable problems of normal people,” even if it is not always the easiest or most obvious course of action. Green is a popular content creator and YouTuber whose work often focuses on science and STEAM issues, and who co-created the educational media company Complexly.

President Kornbluth challenged graduates to be “ambassadors” for the open-minded inquiry and collaborative work that marks everyday life at MIT.

Top accolades

In January, the White House bestowed national medals of science and technology — the country’s highest awards for scientists and engineers — on four MIT professors and an additional alumnus. Moderna, with deep MIT roots, was also recognized.

As in past years, MIT faculty, staff, and alumni were honored with election to the various national academies: the National Academy of Sciences, the National Academy of Engineering, the National Academy of Medicine, and the National Academy of Inventors.

Faculty member Carlo Ratti served as curator of the Venice Biennale’s 19th International Architecture Exhibition.

Members of MIT Video Productions won a New England Emmy Award for their short film on the art and science of hand-forged knives with master bladesmith Bob Kramer.

And at MIT, Dimitris Bertsimas, vice provost for open learning and a professor of operations research, won this year’s Killian Award, the Institute’s highest faculty honor.

New and refreshed spaces

In the heart of campus, the Edward and Joyce Linde Music Building became fully operational to start off the year. In celebration, the Institute hosted Artfinity, a vibrant multiweek exploration of art and ideas, with more than 80 free performing and visual arts events including a film festival, interactive augmented-reality art installations, a simulated lunar landing, and concerts by both student groups and internationally renowned musicians.

Over the summer, the “Outfinite” — the open space connecting Hockfield Court with Massachusetts Avenue — was officially named the L. Rafael Reif Innovation Corridor in honor of President Emeritus L. Rafael Reif, MIT’s 17th president.

And in October, the Undergraduate Advising Center’s bright new home opened in Building 11 along the Infinite Corridor, bringing a welcoming and functional destination for MIT undergraduate students within the Institute’s Main Group.

Student honors and awards

MIT undergraduates earned an impressive number of prestigious awards in 2025. Exceptional students were honored with Rhodes, Gates Cambridge, and Schwarzman scholarships, among others.

A number of MIT student-athletes also helped to secure their team’s first NCAA national championship in Institute history: Women’s track and field won both the indoor national championship and outdoor national championship, while women’s swimming and diving won their national title as well.

Also for the fifth year in a row, MIT students earned all five top spots at the Putnam Mathematical Competition.

Leadership transitions

Several senior administrative leaders took on new roles in 2025. Anantha Chandrakasan was named provost; Paula Hammond was named dean of the School of Engineering; Richard Locke was named dean of the MIT Sloan School of Management; Gaspare LoDuca was named vice president for information systems and technology and CIO; Evelyn Wang was named vice president for energy and climate; and David Darmofal was named vice chancellor for undergraduate and graduate education.

Additional new leadership transitions include: Ana Bakshi was named executive director of the Martin Trust Center for MIT Entrepreneurship; Fikile Brushett was named director of the David H. Koch School of Chemical Engineering Practice; Laurent Demanet was named co-director of the Center for Computational Science and Engineering; Rohit Karnik was named director of the Abdul Latif Jameel Water and Food Systems Lab; Usha Lee McFarling was named director of the Knight Science Journalism Program; C. Cem Tasan was named director of the Materials Research Laboratory; and Jessika Trancik was named director of the Sociotechnical Systems Research Center.

Remembering those we lost

Among MIT community members who died this year were David Baltimore, Juanita Battle, Harvey Kent Bowen, Stanley Fischer, Frederick Greene, Lee Grodzins, John Joannopoulos, Keith Johnson, Daniel Kleppner, Earle Lomon, Nuno Loureiro, Victor K. McElheny, David Schmittlein, Anthony Sinskey, Peter Temin, Barry Vercoe, Rainer Weiss, Alan Whitney, and Ioannis Yannas.

In case you missed it…

Additional top stories from around the Institute in 2025 include a description of the environmental and sustainability implications of generative AI tech and applications; the story of how an MIT professor introduced hundreds of thousands of students to neuroscience with his classic textbook; a look at how MIT entrepreneurs are using AI; a roundup of new books by MIT faculty and staff; and behind the scenes with MIT students who cracked a longstanding egg dilemma. 

In 2025, MIT’s research community had another prolific year filled with exciting scientific and technological advances. To celebrate the achievements of the past 12 months, MIT News highlights some of our most-read stories from this year.

• More powerful concrete “batteries”: MIT researchers combined cement, water, ultra-fine carbon black, and electrolytes to create electron-conducting carbon concrete. The researchers say the material could enable everyday structures like walls, sidewalks, and bridges to store and release electrical energy.
   
• Confirming the famous double-slit experiment: Physicists performed an idealized version of one of the most famous experiments in quantum physics, demonstrating with atomic-level precision the dual nature of light. The experiment confirmed that light exists as both a particle and a wave, though that duality cannot be simultaneously observed.
   
• Periodic table of machine learning: Researchers created a table that reveals connections among more than 20 classical machine-learning algorithms. The table stems from the idea that all algorithms learn a specific kind of relationship between data points. The framework could help scientists fuse different methods to improve existing AI models or come up with new ones.
   
• Photographing “free range” atoms: Physicists captured the first images of individual atoms freely interacting in space. The experiment used single-atom microscopy and ultracold quantum gases to reveal correlations between the particles that had been predicted but never before observed.
   
• Pulling drinking water from air: Engineers developed a window-sized device that acts as an atmospheric water harvester to produce fresh water anywhere. The origami-inspired device uses a hydrogel material that swells to absorb water — it even works in Death Valley, California.
   
• Generative AI versus drug-resistant bacteria: With help from artificial intelligence, researchers designed novel antibiotics that can combat two drug-resistant infections. First, a generative AI algorithm designed more than 35 million compounds. Then, the researchers screened them for antimicrobial properties, discovering drug candidates that are structurally distinct from any existing antibiotics.
   
• Tracking the ozone recovery: A study confirms the Antarctic ozone layer is healing as a direct result of global efforts to reduce ozone-depleting chlorofluorocarbons — chemicals that were used in refrigeration, air conditioning, insulation, and aerosol propellants.
   
• First evidence of “proto Earth”: Scientists discovered extremely rare remnants of an early version of our planet that formed about 4.5 billion years ago, before a colossal collision irreversibly altered its composition and produced the Earth as we know today. The findings will help scientists piece together the primordial starting ingredients that forged early Earth and the rest of the solar system.
   
• Restoring movement with a bionic knee: Researchers developed a bionic knee that can help people with above-the-knee amputations walk faster, climb stairs, and avoid obstacles. In a small study, users navigated more easily and said the limb felt more like a part of their body compared to traditional prostheses.
   
• How people walk in crowds: Mathematicians studied the flow of human crowds and developed a first-of-its-kind way to predict when pedestrian paths will transition from orderly to entangled. The findings could help inform the design of public spaces and promote safe and efficient thoroughfares.

In 2013, Martin Trust Center for MIT Entrepreneurship Managing Director Bill Aulet published “Disciplined Entrepreneurship: 24 Steps to a Successful Startup,” which has since sold hundreds of thousands of copies and been used to teach entrepreneurship at universities around the world. One MIT course where it’s used is 15.366 (Climate and Energy Ventures), where instructors have tweaked the framework over the years. In a new book, “Disciplined Entrepreneurship for Climate and Energy Ventures,” they codify those changes and provide a new blueprint for entrepreneurs working in the climate and energy spaces.

MIT News spoke with lead author and Trust Center Entrepreneur-in-Residence Ben Soltoff, who wrote the book with Aulet, Senior Lecturer Tod Hynes, Senior Lecturer Francis O’Sullivan, and Lecturer Libby Wayman. Soltoff explains why climate and energy entrepreneurship is so challenging and talks about some of the new steps in the book.

Q: What are climate and energy ventures?

A: It’s a broad umbrella. These ventures aren’t all in a specific industry or structured in the same way. They could be software, they could be hardware, or they could be deep tech coming out of labs. This book is also written for people working in government, large corporations, or nonprofits. Each of those folks can benefit from the entrepreneurial framework in this book. We very intentionally refer to them as climate and energy ventures in the book, not just climate and energy startups.

One common theme is meeting the challenge of providing enough energy for current and future needs without exacerbating, or even while reducing, the impact we have on our planet. Generally, climate and energy ventures are less likely to be only software. Many of the solutions we need are around molecules, not bits. A lot of it is breakthrough technology and science from research labs. You could be making a useful fuel, removing CO2 from the atmosphere, or delivering something in a novel way. Your venture might produce a chemical or molecule that’s already being provided and is a commodity. It needs to be not only more sustainable, but better for your customers — either cheaper, more reliable, or more securely delivered. Ultimately, all of these ventures have to provide value. They also often involve physical infrastructure that you have to scale up — not just 10 times or 100 times, but 1,000 times or more — from original lab demonstrations.

Q: How should climate and energy entrepreneurs be thinking about navigating financing and working with the government?

A: One of the major themes of the book is the importance of figuring out if policy is in your favor and constantly applying a policy lens to what you’re building. Finance is another major theme. In climate and energy, these things are fundamental, and we need to consider them from the beginning. We talk about different “valleys of death” — the idea that going from one stage to the next stage requires this jump in time and resources that presents a big challenge. That also relates to the jump in scale of the technology, from a lab scale to something you can produce and sell in a quantity and at a cost the market is interested in. All of that requires financing.

At an early stage, a lot of these ventures are funded through grants and research funding. Later, they start getting early-stage capital — often venture capital. Eventually, as folks are scaling, they move to debt and project financing. Companies need to be very intentional about the type of financing they’re going to pursue and at what stage. We have an entire step on creating a long-term capital plan. Entrepreneurs need to be very clear about the story they’re going to tell investors at different stages. Otherwise, they can paint themselves into a corner and fail to build a company for the next stage of capital they need.

In terms of policy, entrepreneurs should use the policy environment as a filter for selecting a market. We have a story in the book about a startup that switched from working in sub-Saharan Africa to the U.S. after the Inflation Reduction Act passed. As those incentives began disappearing, they still had the option to return to their original market. It’s not ideal for them, but they are still able to build profitable projects. You shouldn’t build a company based on the incentives alone, but you should understand which way the wind is blowing and take advantage of policy when it’s in your favor. That said, policy can always change.

Q: How should climate and energy entrepreneurs select the right market “stepping stones”?

A: Each of the “Disciplined Entrepreneurship” books talks about the importance of selecting customers and listening to your customers. When thinking about their beachhead market, or where to initially focus, climate and energy entrepreneurs need to look for the easiest near-term opportunity to plug in their technology. Subsequent market selection is also driven by technology. Instead of just picking a beachhead market and figuring everything else out later, there often needs to be an intentional choice of what we call market stepping stones. You start by focusing on an initial market in the early days — land and expand — but there needs to be a long-term strategy, so you don’t go down a dead end. These ventures don’t have a lot of flexibility as they build out potentially expensive technologies. Being intentional means having a pathway planned from the beachhead market up to the big prize that makes the entire enterprise worthwhile. The prize means having a big impact but also targeting a big market opportunity.

We have an example in the book of a company that can turn CO2 into useful products. They knew the big prize was turning it into fuel, most likely aviation fuel, but they couldn’t produce at the right volume or cost early on, so they looked at other applications. They started with making vodka from CO2 because it was low-volume and high-margin. Then the pandemic happened, so they made hand sanitizer. Then they made perfume, which had the highest margins of all. By that point, they were ready to start moving into the fuel market. The stepping stones are about figuring out who is willing to buy the simple version of your technology or product and pay a premium. Initially, looking at that company, you might say, “They’re not going to save the planet by selling vodka.” But it was a critical stepping stone to get to the big prize. Long-term thinking is essential for ventures in this space.

One of the biggest risk factors for developing liver cancer is a high-fat diet. A new study from MIT reveals how a fatty diet rewires liver cells and makes them more prone to becoming cancerous.

The researchers found that in response to a high-fat diet, mature hepatocytes in the liver revert to an immature, stem-cell-like state. This helps them to survive the stressful conditions created by the high-fat diet, but in the long term, it makes them more likely to become cancerous.

“If cells are forced to deal with a stressor, such as a high-fat diet, over and over again, they will do things that will help them survive, but at the risk of increased susceptibility to tumorigenesis,” says Alex K. Shalek, director of the Institute for Medical Engineering and Sciences (IMES), the J. W. Kieckhefer Professor in IMES and the Department of Chemistry, and a member of the Koch Institute for Integrative Cancer Research at MIT, the Ragon Institute of MGH, MIT, and Harvard, and the Broad Institute of MIT and Harvard.

The researchers also identified several transcription factors that appear to control this reversion, which they believe could make good targets for drugs to help prevent tumor development in high-risk patients.

Shalek; Ömer Yilmaz, an MIT associate professor of biology and a member of the Koch Institute; and Wolfram Goessling, co-director of the Harvard-MIT Program in Health Sciences and Technology, are the senior authors of the study, which appears today in Cell. MIT graduate student Constantine Tzouanas, former MIT postdoc Jessica Shay, and Massachusetts General Brigham postdoc Marc Sherman are the co-first authors of the paper.

Cell reversion

A high-fat diet can lead to inflammation and buildup of fat in the liver, a condition known as steatotic liver disease. This disease, which can also be caused by a wide variety of long-term metabolic stresses such as high alcohol consumption, may lead to liver cirrhosis, liver failure, and eventually cancer.

In the new study, the researchers wanted to figure out just what happens in cells of the liver when exposed to a high-fat diet — in particular, which genes get turned on or off as the liver responds to this long-term stress.

To do that, the researchers fed mice a high-fat diet and performed single-cell RNA-sequencing of their liver cells at key timepoints as liver disease progressed. This allowed them to monitor gene expression changes that occurred as the mice advanced through liver inflammation, to tissue scarring and eventually cancer.

In the early stages of this progression, the researchers found that the high-fat diet prompted hepatocytes, the most abundant cell type in the liver, to turn on genes that help them survive the stressful environment. These include genes that make them more resistant to apoptosis and more likely to proliferate.

At the same time, those cells began to turn off some of the genes that are critical for normal hepatocyte function, including metabolic enzymes and secreted proteins.

“This really looks like a trade-off, prioritizing what’s good for the individual cell to stay alive in a stressful environment, at the expense of what the collective tissue should be doing,” Tzouanas says.

Some of these changes happened right away, while others, including a decline in metabolic enzyme production, shifted more gradually over a longer period. Nearly all of the mice on a high-fat diet ended up developing liver cancer by the end of the study.

When cells are in a more immature state, it appears that they are more likely to become cancerous if a mutation occurs later on, the researchers say.

“These cells have already turned on the same genes that they’re going to need to become cancerous. They’ve already shifted away from the mature identity that would otherwise drag down their ability to proliferate,” Tzouanas says. “Once a cell picks up the wrong mutation, then it’s really off to the races and they’ve already gotten a head start on some of those hallmarks of cancer.”

The researchers also identified several genes that appear to orchestrate the changes that revert hepatocytes to an immature state. While this study was going on, a drug targeting one of these genes (thyroid hormone receptor) was approved to treat a severe form of steatotic liver disease called MASH fibrosis. And, a drug activating an enzyme that they identified (HMGCS2) is now in clinical trials to treat steatotic liver disease.

Another possible target that the new study revealed is a transcription factor called SOX4, which is normally only active during fetal development and in a small number of adult tissues (but not the liver).

Cancer progression

After the researchers identified these changes in mice, they sought to discover if something similar might be happening in human patients with liver disease. To do that, they analyzed data from liver tissue samples removed from patients at different stages of the disease. They also looked at tissue from people who had liver disease but had not yet developed cancer.

Those studies revealed a similar pattern to what the researchers had seen in mice: The expression of genes needed for normal liver function decreased over time, while genes associated with immature states went up. Additionally, the researchers found that they could accurately predict patients’ survival outcomes based on an analysis of their gene expression patterns.

“Patients who had higher expression of these pro-cell-survival genes that are turned on with high-fat diet survived for less time after tumors developed,” Tzouanas says. “And if a patient has lower expression of genes that support the functions that the liver normally performs, they also survive for less time.”

While the mice in this study developed cancer within a year or so, the researchers estimate that in humans, the process likely extends over a longer span, possibly around 20 years. That will vary between individuals depending on their diet and other risk factors such as alcohol consumption or viral infections, which can also promote liver cells’ reversion to an immature state.

The researchers now plan to investigate whether any of the changes that occur in response to a high-fat diet can be reversed by going back to a normal diet, or by taking weight-loss drugs such as GLP-1 agonists. They also hope to study whether any of the transcription factors they identified could make good targets for drugs that could help prevent diseased liver tissue from becoming cancerous.

“We now have all these new molecular targets and a better understanding of what is underlying the biology, which could give us new angles to improve outcomes for patients,” Shalek says.

The research was funded, in part, by a Fannie and John Hertz Foundation Fellowship, a National Science Foundation Graduate Research Fellowship, the National Institutes of Health, and the MIT Stem Cell Initiative through Foundation MIT.

Aviation’s climate impact is partly due to contrails — condensation that a plane streaks across the sky when it flies through icy and humid layers of the atmosphere. Contrails trap heat that radiates from the planet’s surface, and while the magnitude of this impact is uncertain, several studies suggest contrails may be responsible for about half of aviation’s climate impact.

Pilots could conceivably reduce their planes’ climate impact by avoiding contrail-prone regions, similarly to making altitude adjustments to avoid turbulence. But to do so requires knowing where in the sky contrails are likely to form.

To make these predictions, scientists are studying images of contrails that have formed in the past. Images taken by geostationary satellites are one of the main tools scientists use to develop contrail identification and avoidance systems. 

But a new study shows there are limits to what geostationary satellites can see. MIT engineers analyzed contrail images taken with geostationary satellites, and compared them with images of the same areas taken by low-Earth-orbiting (LEO) satellites. LEO satellites orbit the Earth at lower altitudes and therefore can capture more detail. However, since LEO satellites only snap an image as they fly by, they capture images of the same area far less frequently than geostationary (GEO) satellites, which continuously image the same region of the Earth every few minutes.

The researchers found that geostationary satellites miss about 80 percent of the contrails that appear in LEO imagery. Geostationary satellites mainly see larger contrails that have had time to grow and spread across the atmosphere. The many more contrails that LEO satellites can pick up are often shorter and thinner. These finer threads likely formed immediately from a plane’s engines and are still too small or otherwise not distinct enough for geostationary satellites to discern.

The study highlights the need for a multiobservational approach in developing contrail identification and avoidance systems. The researchers emphasize that both GEO and LEO satellite images have their strengths and limitations. Observations from both sources, as well as images taken from the ground, could provide a more complete picture of contrails and how they evolve.

“With more ‘eyes’ on the sky, we could start to see what a contrail’s life looks like,” says Prakash Prashanth, a research scientist in MIT’s Department of Aeronautics and Astronautics (AeroAstro). “Then you can understand what are its radiative properties over its entire life, and when and why a contrail is climatically important.”

The new study appears today in the journal Geophysical Research Letters. The study’s MIT co-authors include first author Marlene Euchenhofer, a graduate student in AeroAstro; Sydney Parke, an undergraduate student; Ian Waitz, the Jerome C. Hunsaker Professor of Aeronautics and Astronautics and MIT’s vice president of research; and Sebastian Eastham of Imperial College London.

Imaging backbone

Contrails form when the exhaust from planes meets icy, humid air, and the particles from the exhaust act as seeds on which water vapor collects and freezes into ice crystals. As a plane moves forward, it leaves a trail of condensation in its wake that starts as a thin thread that can grow and spread over large distances, lasting for several hours before dissipating.

When it persists, a contrail acts similar to an ice cloud and, as such, can have two competing effects: one in which the contrail is a sort of heat shield, reflecting some incoming radiation from the sun. On the other hand, a contrail can also act as a blanket, absorbing and reflecting back some of the heat from the surface. During the daytime, when the sun is shining, contrails can have both heat shielding and trapping effects. At night, the cloud-like threads have only a trapping, warming effect. On balance, studies have shown that contrails as a whole contribute to warming the planet.

There are multiple efforts underway to develop and test aircraft contrail-avoidance systems to reduce aviation’s climate-warming impact. And scientists are using images of contrails from space to help inform those systems.

“Geostationary satellite images are the workhorse of observations for detecting contrails,” says Euchenhofer. “Because they are at 36,000 kilometers above the surface, they can cover a wide area, and they look at the same point day and night so you can get new images of the same location every five minutes.”

But what they bring in rate and coverage, geostationary satellites lack in clarity. The images they take are about one-fifth the resolution of those taken by LEO satellites. This wouldn’t be a surprise to most scientists. But Euchenhofer wondered how different the geostationary and LEO contrail pictures would look, and what opportunities there might be to improve the picture if both sources could be combined.

“We still think geostationary satellites are the backbone of observation-based avoidance because of the spatial coverage and the high frequency at which we get an image,” she says. “We think that the data could be enhanced if we include observations from LEO and other data sources like ground-based cameras.”

Catching the trail

In their new study, the researchers analyzed contrail images from two satellite imagers: the Advanced Baseline Imager (ABI) aboard a geostationary satellite that is typically used to observe contrails and the higher-resolution Visible Infrared Radiometer Suite (VIIRS), an instrument onboard several LEO satellites.

For each month from December 2023 to November 2024, the team picked out an image of the contiguous United States taken by VIIRS during its flyby. They found corresponding images of the same location, taken at about the same time of day by the geostationary ABI. The images were taken in the infrared spectrum and represented in false color, which enabled the researchers to more easily identify contrails that formed during both the day and night. The researchers then worked by eye, zooming in on each image to identify, outline, and label each contrail they could see.

When they compared the images, they found that GEO images missed about 80 percent of the contrails observed in the LEO images. They also assessed the length and width of contrails in each image and found that GEO images mostly captured larger and longer contrails, while LEO images could also discern shorter, smaller contrails.

“We found 80 percent of the contrails we could see with LEO satellites, we couldn’t see with GEO imagers,” says Prashanth, who is the executive officer of MIT’s Laboratory for Aviation and the Environment. “That does not mean that 80 percent of the climate impact wasn’t captured. Because the contrails we see with GEO imagers are the bigger ones that likely have a bigger climate effect.”

Still, the study highlights an opportunity.

“We want to make sure this message gets across: Geostationary imagers are extremely powerful in terms of the spatial extent they cover and the number of images we can get,” Euchenhofer says. “But solely relying on one instrument, especially when policymaking comes into play, is probably too incomplete a picture to inform science and also airlines regarding contrail avoidance. We really need to fill this gap with other sensors.”

The team says other sensors could include networks of cameras on the ground that under ideal conditions can spot contrails as planes form them in real time. These smaller, “younger” contrails are typically missed by geostationary satellites. Once scientists have these ground-based data, they can match the contrail to the plane and use the plane’s flight data to identify the exact altitude at which the contrail appears. They could then track the contrail as it grows and spreads through the atmosphere, using geostationary images. Eventually, with enough data, scientists could develop an accurate forecasting model, in real time, to predict whether a plane is heading toward a region where contrails might form and persist, and how it could change its altitude to avoid the region.

“People see contrail avoidance as a near-term and cheap opportunity to attack one of the hardest-to-abate sectors in transportation,” Prashanth says. “We don’t have a lot of easy solutions in aviation to reduce our climate impact. But it is premature to do so until we have better tools to determine where in the atmosphere contrails will form, to understand their relative impacts and to verify avoidance outcomes. We have to do this in a careful and rigorous manner, and this is where a lot of these pieces come in.”

This work was supported, in part, by the U.S. Federal Aviation Administration Office of Environment and Energy.

In the past year, two separate experiments in two different materials captured the same confounding scenario: the coexistence of superconductivity and magnetism. Scientists had assumed that these two quantum states are mutually exclusive; the presence of one should inherently destroy the other.

Now, theoretical physicists at MIT have an explanation for how this Jekyll-and-Hyde duality could emerge. In a paper appearing today in the Proceedings of the National Academy of Sciences, the team proposes that under certain conditions, a magnetic material’s electrons could splinter into fractions of themselves to form quasiparticles known as “anyons.” In certain fractions, the quasiparticles should flow together without friction, similar to how regular electrons can pair up to flow in conventional superconductors.

If the team’s scenario is correct, it would introduce an entirely new form of superconductivity — one that persists in the presence of magnetism and involves a supercurrent of exotic anyons rather than everyday electrons.

“Many more experiments are needed before one can declare victory,” says study lead author Senthil Todadri, the William and Emma Rogers Professor of Physics at MIT. “But this theory is very promising and shows that there can be new ways in which the phenomenon of superconductivity can arise.”

What’s more, if the idea of superconducting anyons can be confirmed and controlled in other materials, it could provide a new way to design stable qubits — atomic-scale “bits” that interact quantum mechanically to process information and carry out complex computations far more efficiently than conventional computer bits.

“These theoretical ideas, if they pan out, could make this dream one tiny step within reach,” Todadri says.

The study’s co-author is MIT physics graduate student Zhengyan Darius Shi.

“Anything goes”

Superconductivity and magnetism are macroscopic states that arise from the behavior of electrons. A material is a magnet when electrons in its atomic structure have roughly the same spin, or orbital motion, creating a collective pull in the form of a magnetic field within the material as a whole. A material is a superconductor when electrons passing through, in the form of voltage, can couple up in “Cooper pairs.” In this teamed-up state, electrons can glide through a material without friction, rather than randomly knocking against its atomic latticework.

For decades, it was thought that superconductivity and magnetism should not co-exist; superconductivity is a delicate state, and any magnetic field can easily sever the bonds between Cooper pairs. But earlier this year, two separate experiments proved otherwise. In the first experiment, MIT’s Long Ju and his colleagues discovered superconductivity and magnetism in rhombohedral graphene — a synthesized material made from four or five graphene layers.

“It was electrifying,” says Todadri, who recalls hearing Ju present the results at a conference. “It set the place alive. And it introduced more questions as to how this could be possible.”

Shortly after, a second team reported similar dual states in the semiconducting crystal molybdenium ditelluride (MoTe2). Interestingly, the conditions in which MoTe2 becomes superconductive happen to be the same conditions in which the material exhibits an exotic “fractional quantum anomalous Hall effect,” or FQAH — a phenomenon in which any electron passing through the material should split into fractions of itself. These fractional quasiparticles are known as “anyons.”

Anyons are entirely different from the two main types of particles that make up the universe: bosons and fermions. Bosons are the extroverted particle type, as they prefer to be together and travel in packs. The photon is the classic example of a boson. In contrast, fermions prefer to keep to themselves, and repel each other if they are too near. Electrons, protons, and neutrons are examples of fermions. Together, bosons and fermions are the two major kingdoms of particles that make up matter in the three-dimensional universe.

Anyons, in contrast, exist only in two-dimensional space. This third type of particle was first predicted in the 1980s, and its name was coined by MIT’s Frank Wilczek, who meant it as a tongue-in-cheek reference to the idea that, in terms of the particle’s behavior, “anything goes.”

A few years after anyons were first predicted, physicists such as Robert Laughlin PhD ’79, Wilczek, and others also theorized that, in the presence of magnetism, the quasiparticles should be able to superconduct.

“People knew that magnetism was usually needed to get anyons to superconduct, and they looked for magnetism in many superconducting materials,” Todadri says. “But superconductivity and magnetism typically do not occur together. So then they discarded the idea.”

But with the recent discovery that the two states can, in fact, peacefully coexist in certain materials, and in MoTe2 in particular, Todadri wondered: Could the old theory, and superconducting anyons, be at play?

Moving past frustration

Todadri and Shi set out to answer that question theoretically, building on their own recent work. In their new study, the team worked out the conditions under which superconducting anyons could emerge in a two-dimensional material. To do so, they applied equations of quantum field theory, which describes how interactions at the quantum scale, such as the level of individual anyons, can give rise to macroscopic quantum states, such as superconductivity. The exercise was not an intuitive one, since anyons are known to stubbornly resist moving, let alone superconducting, together.

“When you have anyons in the system, what happens is each anyon may try to move, but it’s frustrated by the presence of other anyons,” Todadri explains. “This frustration happens even if the anyons are extremely far away from each other. And that’s a purely quantum mechanical effect.”

Even so, the team looked for conditions in which anyons might break out of this frustration and move as one macroscopic fluid. Anyons are formed when electrons splinter into fractions of themselves under certain conditions in two-dimensional, single-atom-thin materials, such as MoTe2. Scientists had previously observed that MoTe2 exhibits the FQAH, in which electrons fractionalize, without the help of an external magnetic field.

Todadri and Shi took MoTe2 as a starting point for their theoretical work. They modeled the conditions in which the FQAH phenomenon emerged in MoTe2, and then looked to see how electrons would splinter, and what types of anyons would be produced, as they theoretically increased the number of electrons in the material.

They noted that, depending on the material’s electron density, two types of anyons can form: anyons with either 1/3 or 2/3 the charge of an electron. They then applied equations of quantum field theory to work out how either of the two anyon types would interact, and found that when the anyons are mostly of the 1/3 flavor, they are predictably frustrated, and their movement leads to ordinary metallic conduction. But when anyons are mostly of the 2/3 flavor, this particular fraction encourages the normally stodgy anyons to instead move collectively to form a superconductor, similar to how electrons can pair up and flow in conventional superconductors.

“These anyons break out of their frustration and can move without friction,” Todadri says. “The amazing thing is, this is an entirely different mechanism by which a superconductor can form, but in a way that can be described as Cooper pairs in any other system.”

Their work revealed that superconducting anyons can emerge at certain electron densities. What’s more, they found that when superconducting anyons first emerge, they do so in a totally new pattern of swirling supercurrents that spontaneously appear in random locations throughout the material. This behavior is distinct from conventional superconductors and is an exotic state that experimentalists can look for as a way to confirm the team’s theory. If their theory is correct, it would introduce a new form of superconductivity, through the quantum interactions of anyons.

“If our anyon-based explanation is what is happening in MoTe2, it opens the door to the study of a new kind of quantum matter which may be called ‘anyonic quantum matter,’” Todadri says. “This will be a new chapter in quantum physics.”

This research was supported, in part, by the National Science Foundation. 

MIT has shared the following statement following last night’s announcements by authorities in Rhode Island and Massachusetts about the individual responsible for the murders of Professor Nuno Loureiro at his home in Brookline, Massachusetts, and two students during a mass shooting at Brown University. "We are grateful to all who played a part in identifying and tracking down the suspect in the killing of Prof. Loureiro. Our community continues to mourn and remember Nuno — an incredible scientist, colleague, mentor, and friend. Our thoughts are also with the Brown University community, which suffered so much loss this week.

As the authorities work to answer remaining questions, our continuing position is to refer to the law enforcement agencies and the U.S. Attorney of Massachusetts for information.

For now, our focus is on our community, on Nuno’s family, and all those who knew him.”

Remembering Nuno

• Letter to the MIT community from President Kornbluth (Dec 19)
• MIT News Obituary (Dec. 16)
• Letter to the MIT community (Dec. 16)

 The MIT News obituary will continue to be updated with remembrances from our community members who worked alongside Nuno. In time, the many communities Nuno belonged to will create opportunities to mourn his loss and celebrate his life.This page may be updated as there is additional public information to share.