It’s difficult to build devices that replicate the fluid, precise motion of humans, but that might change if we could pull a few (literal) strings.

At least, that’s the idea behind “cable-driven” mechanisms in which running a string through an object generates streamlined movement across an object’s different parts. Take a robotic finger, for example: You could embed a cable through the palm to the fingertip of this object and then pull it to create a curling motion.

While cable-driven mechanisms can create real-time motion to make an object bend, twist, or fold, they can be complicated and time-consuming to assemble by hand. To automate the process, researchers from MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) have developed an all-in-one 3D printing approach called “Xstrings.” Part design tool, part fabrication method, Xstrings can embed all the pieces together and produce a cable-driven device, saving time when assembling bionic robots, creating art installations, or working on dynamic fashion designs.

In a paper to be presented at the 2025 Conference on Human Factors in Computing Systems (CHI2025), the researchers used Xstrings to print a range of colorful and unique objects that included a red walking lizard robot, a purple wall sculpture that can open and close like a peacock’s tail, a white tentacle that curls around items, and a white claw that can ball up into a fist to grab objects.

To fabricate these eye-catching mechanisms, Xstrings allows users to fully customize their designs in a software program, sending them to a multi-material 3D printer to bring that creation to life. You can automatically print all the device’s parts in their desired locations in one step, including the cables running through it and the joints that enable its intended motion.

MIT CSAIL postdoc and lead author Jiaji Li says that Xstrings can save engineers time and energy, reducing 40 percent of total production time compared to doing things manually. “Our innovative method can help anyone design and fabricate cable-driven products with a desktop bi-material 3D printer,” says Li.

A new twist on cable-driven fabrication

To use the Xstrings program, users first input a design with specific dimensions, like a rectangular cube divided into smaller pieces with a hole in the middle of each one. You can then choose which way its parts move by selecting different “primitives:” bending, coiling (like a spring), twisting (like a screw), or compressing — and the angle of these motions.

For even more elaborate creations, users can incorporate multiple primitives to create intriguing combinations of motions. If you wanted to make a toy snake, you could include several twists to create a “series” combo, in which a single cord drives a sequence of motions. To create the robot claw, the team embedded multiple cables into a “parallel” combination, where several strings are embedded, to enable each finger to close up into a fist.

Beyond fine-tuning the way cable-driven mechanisms move, Xstrings also facilitates how cables are integrated into the object. Users can choose exactly how the strings are secured, in terms of where the “anchor” (endpoint), “threaded areas” (or holes within the structure that the cord passes through), and “exposed point” (where you’d pull to operate the device) are located. With a robot finger, for instance, you could choose the anchor to be located at the fingertip, with a cable running through the finger and a pull tag exposed at the other end.

Xstrings also supports diverse joint designs by automatically placing components that are elastic, compliant, or mechanical. This allows the cable to turn as needed as it completes the device’s intended motion.

Driving unique designs across robotics, art, and beyond

Once users have simulated their digital blueprint for a cable-driven item, they can bring it to life via fabrication. Xstrings can send your design to a fused deposition modeling 3D printer, where plastic is melted down into a nozzle before the filaments are poured out to build structures up layer by layer.

Xstrings uses this technique to lay out cables horizontally and build around them. To ensure their method would successfully print cable-driven mechanisms, the researchers carefully tested their materials and printing conditions.

For example, the researchers found that their strings only broke after being pulled up and down by a mechanical device more than 60,000 times. In another test, the team discovered that printing at 260 degrees Celsius with a speed of 10-20 millimeters per second was ideal for producing their many creative items.

“The Xstrings software can bring a variety of ideas to life,” says Li. “It enables you to produce a bionic robot device like a human hand, mimicking our own gripping capabilities. You can also create interactive art pieces, like a cable-driven sculpture with unique geometries, and clothes with adjustable flaps. One day, this technology could enable the rapid, one-step creation of cable-driven robots in outer space, even within highly confined environments such as space stations or extraterrestrial bases.”

The team’s approach offers plenty of flexibility and a noticeable speed boost to fabricating cable-driven objects. It creates objects that are rigid on the outside, but soft and flexible on the inside; in the future, they may look to develop objects that are soft externally but rigid internally, much like humans’ skin and bones. They’re also considering using more resilient cables, and, instead of just printing strings horizontally, embedding ones that are angled or even vertical.

Li wrote the paper with Zhejiang University master’s student Shuyue Feng; Tsinghua University master’s student Yujia Liu; Zhejiang University assistant professor and former MIT Media Lab visiting researcher Guanyun Wang; and three CSAIL members: Maxine Perroni-Scharf, an MIT PhD student in electrical engineering and computer science; Emily Guan, a visiting researcher; and senior author Stefanie Mueller, the TIBCO Career Development Associate Professor in the MIT departments of Electrical Engineering and Computer Science and Mechanical Engineering, and leader of the HCI Engineering Group.

This research was supported, in part, by a postdoctoral research fellowship from Zhejiang University, and the MIT-GIST Program.

Within the human brain, a network of regions has evolved to process language. These regions are consistently activated whenever people listen to their native language or any language in which they are proficient.

A new study by MIT researchers finds that this network also responds to languages that are completely invented, such as Esperanto, which was created in the late 1800s as a way to promote international communication, and even to languages made up for television shows such as “Star Trek” and “Game of Thrones.”

To study how the brain responds to these artificial languages, MIT neuroscientists convened nearly 50 speakers of these languages over a single weekend. Using functional magnetic resonance imaging (fMRI), the researchers found that when participants listened to a constructed language in which they were proficient, the same brain regions lit up as those activated when they processed their native language.

“We find that constructed languages very much recruit the same system as natural languages, which suggests that the key feature that is necessary to engage the system may have to do with the kinds of meanings that both kinds of languages can express,” says Evelina Fedorenko, an associate professor of neuroscience at MIT, a member of MIT’s McGovern Institute for Brain Research and the senior author of the study.

The findings help to define some of the key properties of language, the researchers say, and suggest that it’s not necessary for languages to have naturally evolved over a long period of time or to have a large number of speakers.

“It helps us narrow down this question of what a language is, and do it empirically, by testing how our brain responds to stimuli that might or might not be language-like,” says Saima Malik-Moraleda, an MIT postdoc and the lead author of the paper, which appears this week in the Proceedings of the National Academy of Sciences.

Convening the conlang community

Unlike natural languages, which evolve within communities and are shaped over time, constructed languages, or “conlangs,” are typically created by one person who decides what sounds will be used, how to label different concepts, and what the grammatical rules are.

Esperanto, the most widely spoken conlang, was created in 1887 by Ludwik Zamenhok, who intended it to be used as a universal language for international communication. Currently, it is estimated that around 60,000 people worldwide are proficient in Esperanto.

In previous work, Fedorenko and her students have found that computer programming languages, such as Python — another type of invented language — do not activate the brain network that is used to process natural language. Instead, people who read computer code rely on the so-called multiple demand network, a brain system that is often recruited for difficult cognitive tasks.

Fedorenko and others have also investigated how the brain responds to other stimuli that share features with language, including music and nonverbal communication such as gestures and facial expressions.

“We spent a lot of time looking at all these various kinds of stimuli, finding again and again that none of them engage the language-processing mechanisms,” Fedorenko says. “So then the question becomes, what is it that natural languages have that none of those other systems do?”

That led the researchers to wonder if artificial languages like Esperanto would be processed more like programming languages or more like natural languages. Similar to programming languages, constructed languages are created by an individual for a specific purpose, without natural evolution within a community. However, unlike programming languages, both conlangs and natural languages can be used to convey meanings about the state of the external world or the speaker’s internal state.

To explore how the brain processes conlangs, the researchers invited speakers of Esperanto and several other constructed languages to MIT for a weekend conference in November 2022. The other languages included Klingon (from “Star Trek”), Na’vi (from “Avatar”), and two languages from “Game of Thrones” (High Valyrian and Dothraki). For all of these languages, there are texts available for people who want to learn the language, and for Esperanto, Klingon, and High Valyrian, there is even a Duolingo app available.

“It was a really fun event where all the communities came to participate, and over a weekend, we collected all the data,” says Malik-Moraleda, who co-led the data collection effort with former MIT postbac Maya Taliaferro, now a PhD student at New York University.

During that event, which also featured talks from several of the conlang creators, the researchers used fMRI to scan 44 conlang speakers as they listened to sentences from the constructed language in which they were proficient. The creators of these languages — who are co-authors on the paper — helped construct the sentences that were presented to the participants.

While in the scanner, the participants also either listened to or read sentences in their native language, and performed some nonlinguistic tasks for comparison. The researchers found that when people listened to a conlang, the same language regions in the brain were activated as when they listened to their native language.

Common features

The findings help to identify some of the key features that are necessary to recruit the brain’s language processing areas, the researchers say. One of the main characteristics driving language responses seems to be the ability to convey meanings about the interior and exterior world — a trait that is shared by natural and constructed languages, but not programming languages.

“All of the languages, both natural and constructed, express meanings related to inner and outer worlds. They refer to objects in the world, to properties of objects, to events,” Fedorenko says. “Whereas programming languages are much more similar to math. A programming language is a symbolic generative system that allows you to express complex meanings, but it’s a self-contained system: The meanings are highly abstract and mostly relational, and not connected to the real world that we experience.”

Some other characteristics of natural languages, which are not shared by constructed languages, don’t seem to be necessary to generate a response in the language network.

“It doesn’t matter whether the language is created and shaped over time by a community of speakers, because these constructed languages are not,” Malik-Moraleda says. “It doesn’t matter how old they are, because conlangs that are just a decade old engage the same brain regions as natural languages that have been around for many hundreds of years.”

To further refine the features of language that activate the brain’s language network, Fedorenko’s lab is now planning to study how the brain responds to a conlang called Lojban, which was created by the Logical Language Group in the 1990s and was designed to prevent ambiguity of meanings and promote more efficient communication.

The research was funded by MIT’s McGovern Institute for Brain Research, Brain and Cognitive Sciences Department, the Simons Center for the Social Brain, the Frederick A. and Carole J. Middleton Career Development Professorship, and the U.S. National Institutes of Health.

Really interesting research: “How WEIRD is Usable Privacy and Security Research?” by Ayako A. Hasegawa Daisuke Inoue, and Mitsuaki Akiyama:

Abstract: In human factor fields such as human-computer interaction (HCI) and psychology, researchers have been concerned that participants mostly come from WEIRD (Western, Educated, Industrialized, Rich, and Democratic) countries. This WEIRD skew may hinder understanding of diverse populations and their cultural differences. The usable privacy and security (UPS) field has inherited many research methodologies from research on human factor fields. We conducted a literature review to understand the extent to which participant samples in UPS papers were from WEIRD countries and the characteristics of the methodologies and research topics in each user study recruiting Western or non-Western participants. We found that the skew toward WEIRD countries in UPS is greater than that in HCI. Geographic and linguistic barriers in the study methods and recruitment methods may cause researchers to conduct user studies locally. In addition, many papers did not report participant demographics, which could hinder the replication of the reported studies, leading to low reproducibility. To improve geographic diversity, we provide the suggestions including facilitate replication studies, address geographic and linguistic issues of study/recruitment methods, and facilitate research on the topics for non-WEIRD populations...

The HHS secretary has fought mercury pollution for years. He’s now in an administration that wants to make it easier for industries to dump it into the air and water.

The Trump administration says it terminated $20 billion of Biden-era grants because some recipients have senior staffers who served in the Biden or Obama administrations.

Legislation sponsored by a former Duke Energy executive would eliminate a 2030 emissions goal.

Pierre Poilievre is likely to run against Liberal Prime Minister Mark Carney, who just removed a carbon tax. Poilievere pledged Monday to kill a second carbon fee.

The insurance company is trying to prevent a “dire” financial situation that executives say could force them to drop more California policies.

Former track star Sebastian Coe said he stood “full square” with 400 athletes who urged International Olympic Committee candidates to treat climate as a priority.

Climate change raises risks for farmers: Hotter weather hurts yields and longer rainy seasons trigger the spread of fungus and deadly pests.

The country's concern is that a debt-for-nature swap could “send the wrong message to the markets and make our financial situation worse.”

Prototyping large structures with integrated electronics, like a chair that can monitor someone’s sitting posture, is typically a laborious and wasteful process.

One might need to fabricate multiple versions of the chair structure via 3D printing and laser cutting, generating a great deal of waste, before assembling the frame, grafting sensors and other fragile electronics onto it, and then wiring it up to create a working device.

If the prototype fails, the maker will likely have no choice but to discard it and go back to the drawing board.

MIT researchers have come up with a better way to iteratively design large and sturdy interactive structures. They developed a rapid development platform that utilizes reconfigurable building blocks with integrated electronics that can be assembled into complex, functional devices. Rather than building electronics into a structure, the electronics become the structure.

These lightweight three-dimensional lattice building blocks, known as voxels, have high strength and stiffness, along with integrated sensing, response, and processing abilities that enable users without mechanical or electrical engineering expertise to rapidly produce interactive electronic devices.

The voxels, which can be assembled, disassembled, and reconfigured almost infinitely into various forms, cost about 50 cents each.

The prototyping platform, called VIK (Voxel Invention Kit), includes a user-friendly design tool that enables end-to-end prototyping, allowing a user to simulate the structure’s response to mechanical loads and iterate on the design as needed.

“This is about democratizing access to functional interactive devices. With VIK, there is no 3D printing or laser cutting required. If you just have the voxel faces, you are able to produce these interactive structures anywhere you want,” says Jack Forman, an MIT graduate student in media arts and sciences and affiliate of the MIT Center for Bits and Atoms (CBA) and the MIT Media Lab, and co-lead author of a paper on VIK.

Forman is joined on the paper by co-lead author and fellow graduate student Miana Smith; graduate student Amira Abdel-Rahman; and senior author Neil Gershenfeld, an MIT professor and director of the CBA. The research will be presented at the Conference on Human Factors in Computing Systems.

Functional building blocks

VIK builds upon years of work in the CBA to develop discrete, cellular building blocks called voxels. One voxel, an aluminum cuboctahedra lattice (which has eight triangular faces and six square faces), is strong enough to support 228 kilograms, or about the weight of an upright piano.

Instead of being 3D printed, milled, or laser cut, voxels are assembled into largescale, strong, durable structures like airplane components or wind turbines that can respond to their environments.

The CBA team merged voxels other work in their lab centered on interconnected electrical components, yielding voxels with structural electronics. Assembling these functional voxels generates structures that can transmit data and power, as well as mechanical forces, without the need for wires.

They used these electromechanical building blocks to develop VIK.

“It was an interesting challenge to think about adapting a lot of our previous work, which has been about hitting hard engineering metrics, into a user-friendly system that makes sense and is fun and easy for people to work with,” Smith says.

For instance, they made the voxel design larger so the lattice structures are easier for human hands to assemble and disassemble. They also added aluminum cross-bracing to the units to improve their strength and stability.

In addition, VIK voxels have a reversible, snap-fit connection so a user can seamlessly assemble them without the need for additional tools, in contrast to some prior voxel designs that used rivets as fasteners.

“We designed the voxel faces to permit only the correct connections. That means that, if you are building with voxels, you are guaranteed to be building the correct wiring harness. Once you finish your device, you can just plug it in and it will work,” says Smith.

Wiring harnesses can add significant cost to functional systems and can often be a source of failure.

An accessible prototyping platform

To help users who have minimal engineering expertise create a wide array of interactive devices, the team developed a user-friendly interface to simulate 3D voxel structures.

The interface includes a Finite Element Analysis (FEA) simulation model that enables users to draw out a structure and simulate the forces and mechanical loads that will be applied to it. It adds colors to an animation of the user’s device to identify potential points of failure.

“We created what is essentially a ‘Minecraft’ for voxel applications. You don’t need a good sense of civil engineering or truss analysis to verify that the structure you are making is safe. Anyone can build something with VIK and have confidence in it,” Forman says.

Users can also easily integrate off-the-shelf modules, like speakers, sensors, or actuators, into their device. VIK emphasizes flexibility, enabling makers to use the types of microcontrollers they are comfortable with.

“The next evolution of electronics will be in three-dimensional space and the Voxel Invention Kit (VIK) is the stepping stone that will enable users, designers, and innovators a way to visualize and integrate electronics directly into structures,” says Victor Zaderej, manager of advanced electronics packaging technology at Molex, a manufacturer of electronic, electrical, and fiber optic connectivity systems. “Think of the VIK as the merging of a LEGO building kit and an electronics breadboard. When creative engineers and designers begin thinking about potential applications, the opportunities and unique products that will be enabled will be limitless.”

Using the design tool for feedback, a maker can rapidly change the configuration of voxels to adjust a prototype or disassemble the structure to build something new. If the user eventually wishes to discard the device, the aluminum voxels are fully recyclable.

This reconfigurability and recyclability, along with the high strength, high stiffness, light weight, and integrated electronics of the voxels, could make VIK especially well-suited for applications such as theatrical stage design, where stage managers want to support actors safely with customizable set pieces that might only exist for a few days.

And by enabling the rapid-prototyping of large, complex structures, VIK could also have future applications in areas like space fabrication or in the development of smart buildings and intelligent infrastructure for sustainable cities.

But for the researchers, perhaps the most important next step will be to get VIK out into the world to see what users come up with.

“These voxels are now so readily available that someone can use them in their day-to-day life. It will be exciting to see what they can do and create with VIK,” adds Forman.

California legislators have begun debating a bill (A.B. 412) that would require AI developers to track and disclose every registered copyrighted work used in AI training. At first glance, this might sound like a reasonable step toward transparency. But it’s an impossible standard that could crush small AI startups and developers while giving big tech firms even more power.

A Burden That Small Developers Can’t Bear

The AI landscape is in danger of being dominated by large companies with deep pockets. These big names are in the news almost daily. But they’re far from the only ones – there are dozens of AI companies with fewer than 10 employees trying to build something new in a particular niche. 

This bill demands that creators of any AI model–even a two-person company or a hobbyist tinkering with a small software build– identify copyrighted materials used in training.  That requirement will be incredibly onerous, even if limited just to works registered with the U.S. Copyright Office. The registration system is a cumbersome beast at best–neither machine-readable nor accessible, it’s more like a card catalog than a database–that doesn’t offer information sufficient to identify all authors of a work,  much less help developers to reliably match works in a training set to works in the system.

Even for major tech companies, meeting these new obligations  would be a daunting task. For a small startup, throwing on such an impossible requirement could be a death sentence. If A.B. 412 becomes law, these smaller players will be forced to devote scarce resources to an unworkable compliance regime instead of focusing on development and innovation. The risk of lawsuits—potentially from copyright trolls—would discourage new startups from even attempting to enter the field.

A.I. Training Is Like Reading And It’s Very Likely Fair Use 

A.B. 412 starts from a premise that’s both untrue and harmful to the public interest: that reading, scraping or searching of open web content shouldn’t be allowed without payment. In reality, courts should, and we believe will, find that the great majority of this activity is fair use. 

It’s now bedrock internet law principle that some forms of copying content online are transformative, and thus legal fair use. That includes reproducing thumbnail images for image search, or snippets of text to search books. 

The U.S. copyright system is meant to balance innovation with creator rights, and courts are still working through how copyright applies to AI training. In most of the AI cases, courts have yet to consider—let alone decide—how fair use applies. A.B. 412 jumps the gun, preempting this process and imposing a vague, overly broad standard that will do more harm than good.

Importantly, those key court cases are all federal. The U.S. Constitution makes it clear that copyright is governed by federal law, and A.B. 412 improperly attempts to impose state-level copyright regulations on an issue still in flux. 

A.B. 412 Is A Gift to Big Tech

The irony of A.B. 412 is that it won’t stop AI development—it will simply consolidate it in the hands of the largest corporations. Big tech firms already have the resources to navigate complex legal and regulatory environments, and they can afford to comply (or at least appear to comply) with A.B. 412’s burdensome requirements. Small developers, on the other hand, will either be forced out of the market or driven into partnerships where they lose their independence. The result will be less competition, fewer innovations, and a tech landscape even more dominated by a handful of massive companies.

If lawmakers are able to iron out some of the practical problems with A.B. 412 and pass some version of it, they may be able to force programmers to research–and effectively, pay off–copyright owners before they even write a line of code. If that’s the outcome in California, Big Tech will not despair. They’ll celebrate. Only a few companies own large content libraries or can afford to license enough material to build a deep learning model. The possibilities for startups and small programmers will be so meager, and competition will be so limited, that profits for big incumbent companies will be locked in for a generation. 

If you are a California resident and want to speak out about A.B. 412, you can find and contact your legislators through this website. 

The MIT women's track and field team won its first NCAA Division III National Championship in program history on Saturday, March 15, at the 2025 NCAA Division III Track and Field Championships, hosted by Nazareth College in Rochester, New York.

The Engineers, who entered the meet as the top-ranked team in the nation, scored the most points ever scored by an MIT women's team at a national indoor meet. They finished with 49 points, which earned them a first place finish in a field of 62. They were ahead of Washington University, with 45.5 points; the University of Wisconsin at La Crosse, with 37 points; Loras College, with 32 points; and the State University of New York at Geneseo, with 29 points.

“This was such a fun and exciting outcome, and what our team has been working toward all year,” says Julie Heyde, MIT director of track and field and head coach of cross country and track and field. “Since last year, even, the team knew they had a possibility of being national champs. We didn't gear only toward this goal; we have been very process-driven, and that's why this team win is so special. Each and every person competed for each other, representing a total team culture.” 

Field events

Senior Alexis Boykin's (Clayton, Ohio) third attempt in the shot put was the mark to beat, as the defending national champion registered a mark of 15.31 meters. Boykin also repeated as the indoor national champion in the shot put, which gave her two titles on the weekend and her seventh individual NCAA national championship. 

Senior Emily Ball (Des Moines, Iowa) set a new personal record with a mark of 14.19m (46 feet, 6-3/4 inches) to finish in sixth and earn All-American honors. Ball's second throw was the best attempt for the MIT senior, earning the Engineers three valuable points in the team standings. 

Junior Nony Otu Ugwu (Katy, Texas) finished ninth in the first flight of the triple jump and did not advance to the final. Otu Ugwu's best mark came on her second jump with a mark of 11.78m (38 feet, 7-3/4 inches).

Running events

Graduate student Gillian Roeder (Delmar, New York) finished fifth in the mile event in a hard-fought race, earning All-America honors with a time of 4:51.97.

With MIT on the verge of clinching the national title, Roeder, senior Christina Crow (Mercer Island, Washington), and juniors Rujuta Sane (Chandler, Arizona) and Kate Sanderson (West Hartford, Connecticut) took to the track in the 3,000-meter event. Sane finished 20th in 10:02.86, with Roeder taking 16th in 9:56.02. Crow and Sanderson held in the middle of the pack for most of the race before Sanderson made a late move, taking over sixth place with just a few laps remaining. Sanderson would hold the position to earn three points and clinch the national championship. Crow took 11th in 9:44.99.

Other numbers of note

Otu Ugwu was making her second appearance at indoor nationals and her third overall NCAA appearance. She was 14th in the triple jump at both the indoor and outdoor national championship last year. Roeder was running in the final in the mile for the first time since 2023 indoor nationals, where she also finished fifth. Sanderson qualified for indoor nationals in the 5,000 meters in both 2023 and 2024, but Saturday was her first All-American after finishing 16th in 2024 and 20th in 2023.

MIT will head outside in two weeks, opening the outdoor track and field season Thursday-Saturday, March 27-29, at the Raleigh Relays, hosted by North Carolina State University in Raleigh.

A version of this article first appeared on the MIT Athletics website. 

When you’re challenging a century-old assumption, you’re bound to meet a bit of resistance. That’s exactly what John Joannopoulos and his group at MIT faced in 1998, when they put forth a new theory on how materials can be made to bend light in entirely new ways.

“Because it was such a big difference in what people expected, we wrote down the theory for this, but it was very difficult to get it published,” Joannopoulos told a capacity crowd in MIT’s Huntington Hall on Friday, as he delivered MIT’s James R. Killian, Jr. Faculty Achievement Award Lecture.

Joannopoulos’ theory offered a new take on a type of material known as a one-dimensional photonic crystal. Photonic crystals are made from alternating layers of refractive structures whose arrangement can influence how incoming light is reflected or absorbed.

In 1887, the English physicist John William Strutt, better known as the Lord Rayleigh, established a theory for how light should bend through a similar structure composed of multiple refractive layers. Rayleigh predicted that such a structure could reflect light, but only if that light is coming from a very specific angle. In other words, such a structure could act as a mirror for light shining from a specific direction only.

More than a century later, Joannopoulos and his group found that, in fact, quite the opposite was true. They proved in theoretical terms that, if a one-dimensional photonic crystal were made from layers of materials with certain “refractive indices,” bending light to different degrees, then the crystal as a whole should be able to reflect light coming from any and all directions. Such an arrangement could act as a “perfect mirror.”

The idea was a huge departure from what scientists had long assumed, and as such, when Joannopoulos submitted the research for peer review, it took some time for the journal, and the community, to come around. But he and his students kept at it, ultimately verifying the theory with experiments.

That work led to a high-profile publication, which helped the group focus the idea into a device: Using the principles that they laid out, they effectively fabricated a perfect mirror and folded it into a tube to form a hollow-core fiber. When they shone light through, the inside of the fiber reflected all the light, trapping it entirely in the core as the light pinged through the fiber. In 2000, the team launched a startup to further develop the fiber into a flexible, highly precise and minimally invasive “photonics scalpel,” which has since been used in hundreds of thousands of medical procedures including a surgeries of the brain and spine.

“And get this: We have estimated more than 500,000 procedures across hospitals in the U.S. and abroad,” Joannopoulos proudly stated, to appreciative applause.

Joannopoulos is the recipient of the 2024-2025 James R. Killian, Jr. Faculty Achievement Award, and is the Francis Wright Davis Professor of Physics and director of the Institute for Soldier Nanotechnologies at MIT. In response to an audience member who asked what motivated him in the face of initial skepticism, he replied, “You have to persevere if you believe what you have is correct.”

Immeasurable impact

The Killian Award was established in 1971 to honor MIT’s 10th president, James Killian. Each year, a member of the MIT faculty is honored with the award in recognition of their extraordinary professional accomplishments.

Joannopoulos received his PhD from the University of California at Berkeley in 1974, then immediately joined MIT’s physics faculty. In introducing his lecture, Mary Fuller, professor of literature and chair of the MIT faculty, noted: “If you do the math, you’ll know he just celebrated 50 years at MIT.” Throughout that remarkable tenure, Fuller noted Joannopoulos’ profound impact on generations of MIT students.

“We recognize you as a leader, a visionary scientist, beloved mentor, and a believer in the goodness of people,” Fuller said. “Your legendary impact at MIT and the broader scientific community is immeasurable.”

Bending light

In his lecture, which he titled “Working at the Speed of Light,” Joannopoulos took the audience through the basic concepts underlying photonic crystals, and the ways in which he and others have shown that these materials can bend and twist incoming light in a controlled way.

As he described it, photonic crystals are “artificial materials” that can be designed to influence the properties of photons in a way that’s similar to how physical features in semiconductors affect the flow of electrons. In the case of semiconductors, such materials have a specific “band gap,” or a range of energies in which electrons cannot exist.

In the 1990s, Joannopoulos and others wondered whether the same effects could be realized for optical materials, to intentionally reflect, or keep out, some kinds of light while letting others through. And even more intriguing: Could a single material be designed such that incoming light pinballs away from certain regions in a material in predesigned paths?

“The answer was a resounding yes,” he said.

Joannopoulos described the excitement within the emerging field by quoting an editor from the journal Nature, who wrote at the time: “If only it were possible to make materials in which electromagnetic waves cannot propagate at certain frequencies, all kinds of almost-magical things would be possible.”

Joannopoulos and his group at MIT began in earnest to elucidate the ways in which light interacts with matter and air. The team worked first with two-dimensional photonic crystals made from a horizontal matrix-like pattern of silicon dots surrounded by air. Silicon has a high refractive index, meaning it can greatly bend or reflect light, while air has a much lower index. Joannopoulos predicted that the silicon could be patterned to ping light away, forcing it to travel through the air in predetermined paths.

In multiple works, he and his students showed through theory and experiments that they could design photonic crystals to, for instance, bend incoming light by 90 degrees and force light to circulate only at the edges of a crystal under an applied magnetic field.

“Over the years there have been quite a few examples we’ve discovered of very anomalous, strange behavior of light that cannot exist in normal objects,” he said.

In 1998, after showing that light can be reflected from all directions from a stacked, one-dimensional photonic crystal, he and his students rolled the crystal structure into a fiber, which they tested in a lab. In a video that Joannopoulos played for the audience, a student carefully aimed the end of the long, flexible fiber at a sheet of material made from the same material as the fiber’s casing. As light pumped through the multilayered photonic lining of the fiber and out the other end, the student used the light to slowly etch a smiley face design in the sheet, drawing laughter from the crowd.

As the video demonstrated, although the light was intense enough to melt the material of the fiber’s coating, it was nevertheless entirely contained within the fiber’s core, thanks to the multilayered design of its photonic lining. What’s more, the light was focused enough to make precise patterns when it shone out of the fiber.

“We had originally developed this [optical fiber] as a military device,” Joannopoulos said. “But then the obvious choice to use it for the civilian population was quite clear.”

“Believing in the goodness of people and what they can do”

He and others co-founded Omniguide in 2000, which has since grown into a medical device company that develops and commercializes minimally invasive surgical tools such as the fiber-based “photonics scalpel.” In illustrating the fiber’s impact, Joannopoulos played a news video, highlighting the fiber’s use in performing precise and effective neurosurgery. The optical scalpel has also been used to perform procedures in larynology, head and neck surgery, and gynecology, along with brain and spinal surgeries.

Omniguide is one of several startups that Joannopoulos has helped found, along with Luminus Devices, Inc., WiTricity Corporation, Typhoon HIL, Inc., and Lightelligence. He is author or co-author of over 750 refereed journal articles, four textbooks, and 126 issued U.S. patents. He has earned numerous recognitions and awards, including his election to the National Academy of Sciences and the American Academy of Arts and Sciences.

The Killian Award citation states: “Professor Joannopoulos has been a consistent role model not just in what he does, but in how he does it. … Through all these individuals he has impacted — not to mention their academic descendants — Professor Joannopoulos has had a vast influence on the development of science in recent decades.”

At the end of the talk, Yoel Fink, Joannopoulos’ former student and frequent collaborator, who is now professor of materials science, asked Joannopoulos how, particularly in current times, he has been able to “maintain such a positive and optimistic outlook, of humans and human nature.”

“It’s a matter of believing in the goodness of people and what they can do, what they accomplish, and giving an environment where they’re working in, where they feel extermely comfortable,” Joannopoulos offered. “That includes creating a sense of trust between the faculty and the students, which is key. That helps enormously.”

New paper: “GPU Assisted Brute Force Cryptanalysis of GPRS, GSM, RFID, and TETRA: Brute Force Cryptanalysis of KASUMI, SPECK, and TEA3.”

Abstract: Key lengths in symmetric cryptography are determined with respect to the brute force attacks with current technology. While nowadays at least 128-bit keys are recommended, there are many standards and real-world applications that use shorter keys. In order to estimate the actual threat imposed by using those short keys, precise estimates for attacks are crucial.

In this work we provide optimized implementations of several widely used algorithms on GPUs, leading to interesting insights on the cost of brute force attacks on several real-word applications...

Olivier Blanchard PhD ’77, the Robert M. Solow Professor of Economics Emeritus, has been named a winner of the 2025 BBVA Foundation Frontiers of Knowledge Award in Economics, Finance and Management for “profoundly influencing modern macroeconomic analysis by establishing rigorous foundations for the study of business cycle fluctuations,” as described in the BBVA Foundation’s award citation.

Blanchard, who is also senior fellow at the Peterson Institute for International Economics, shares the award with MIT alumni Jordi Galí PhD ’89 of the Centre de Recerca en Economia Internacional and Pompeu Fabra University in Spain and Michael Woodford PhD ’83 of Columbia University. The three economists were instrumental in developing the New Keynesian model, now widely taught and applied in central banking policy around the world.

The framework builds on classical Keynesian models in part by introducing the role of consumer expectations to macroeconomic policy analysis — in short, using the public’s perception of the future to help inform current policy. The model’s unconventional tools, including greater transparency around monetary policy, were tested by policymakers following the burst of the dotcom bubble in the early 2000s and applied by the Federal Reserve and European Central Bank in response to the 2008 financial crisis.

Blanchard played a foundational role in the development of New Keynesian economics, beginning with a 1987 paper coauthored with Princeton University’s Nobuhiro Kiyotaki (also a Frontiers of Knowledge laureate) on the effects of monetary policy under monopolistic competition. A decade later, Woodford described optimal monetary policy within the New Keynesian framework, laying key theoretical groundwork for the model, and Galí extended and synthesized the framework, ultimately resulting in a blueprint for designing optimal monetary policy.

Blanchard, who joined the MIT faculty in 1983 and served as head of the Department of Economics from 1998 to 2003, advised and taught decades of macroeconomics students at MIT, including Galí. As chief economist of the International Monetary Fund from 2008 to 2015, Blanchard used his framework to help design policy during the Global Financial Crisis and the Euro debt crisis. Blanchard’s leadership as a scholar, student advisor, teacher, and policy advisor is at the heart of the trio’s prize-winning research.

MIT Professor Jonathan Gruber, current head of the economics department, praises Blanchard’s multifaceted contributions.

“Olivier is not only an amazing macroeconomist whose work continues to have profound influence in this time of global macroeconomic uncertainty,” says Gruber, “but also a pillar of the department. His leadership in research and enormous dedication to our program were central in carrying forward the legacy of the department’s early greats and making MIT Economics what it is today.”

Blanchard, Galí, and Woodford share the award’s 400,000-euro prize and will be formally honored at a ceremony in Bilbao, Spain, in June.

The BBVA Foundation works to support scientific research and cultural creation, disseminate knowledge and culture, and recognize talent and innovation, focusing on five strategic areas: environment, biomedicine and health, economy and society, basic sciences and technology, and culture. The Frontiers of Knowledge Awards, spanning eight prize categories, recognize world-class research and cultural creation and aim to celebrate and promote the value of knowledge as a global public good.

Since 2009, the BBVA has given awards to more than a dozen MIT faculty members, including MIT economist Daron Acemoglu, as well as to the Abdul Latif Jameel Poverty Action Lab (J-PAL), led by MIT economists Abhijit Banerjee, Esther Duflo, and Ben Olken.

Companies that were drawn by the law's tax credits to build U.S. factories are wondering if the benefits will escape the president's ideological clampdowns.

Washington state may also see its carbon auction prices decrease if it links up with California's cap-and-trade market.

A planned project in Texas could be the world's first direct air capture development to rely primarily on behind-the-meter electricity.