This sound-suppressing silk can create quiet spaces

We are living in a very noisy world. From the hum of traffic outside your window to the next-door neighbor’s blaring TV to sounds from a co-worker’s cubicle, unwanted noise remains a resounding problem.

To cut through the din, an interdisciplinary collaboration of researchers from MIT and elsewhere developed a sound-suppressing silk fabric that could be used to create quiet spaces.

The fabric, which is barely thicker than a human hair, contains a special fiber that vibrates when a voltage is applied to it. The researchers leveraged those vibrations to suppress sound in two different ways.

In one, the vibrating fabric generates sound waves that interfere with an unwanted noise to cancel it out, similar to noise-canceling headphones, which work well in a small space like your ears but do not work in large enclosures like rooms or planes.

In the other, more surprising technique, the fabric is held still to suppress vibrations that are key to the transmission of sound. This prevents noise from being transmitted through the fabric and quiets the volume beyond. This second approach allows for noise reduction in much larger spaces like rooms or cars.

By using common materials like silk, canvas, and muslin, the researchers created noise-suppressing fabrics which would be practical to implement in real-world spaces. For instance, one could use such a fabric to make dividers in open workspaces or thin fabric walls that prevent sound from getting through.

“Noise is a lot easier to create than quiet. In fact, to keep noise out we dedicate a lot of space to thick walls. [First author] Grace’s work provides a new mechanism for creating quiet spaces with a thin sheet of fabric,” says Yoel Fink, a professor in the departments of Materials Science and Engineering and Electrical Engineering and Computer Science, a Research Laboratory of Electronics principal investigator, and senior author of a paper on the fabric.

The study’s lead author is Grace (Noel) Yang SM ’21, PhD ’24. Co-authors include MIT graduate students Taigyu Joo, Hyunhee Lee, Henry Cheung, and Yongyi Zhao; Zachary Smith, the Robert N. Noyce Career Development Professor of Chemical Engineering at MIT; graduate student Guanchun Rui and professor Lei Zhu of Case Western University; graduate student Jinuan Lin and Assistant Professor Chu Ma of the University of Wisconsin at Madison; and Latika Balachander, a graduate student at the Rhode Island School of Design. An open-access paper about the research appeared recently in Advanced Materials.

Silky silence

The sound-suppressing silk builds off the group’s prior work to create fabric microphones.

In that research, they sewed a single strand of piezoelectric fiber into fabric. Piezoelectric materials produce an electrical signal when squeezed or bent. When a nearby noise causes the fabric to vibrate, the piezoelectric fiber converts those vibrations into an electrical signal, which can capture the sound.

In the new work, the researchers flipped that idea to create a fabric loudspeaker that can be used to cancel out soundwaves.

“While we can use fabric to create sound, there is already so much noise in our world. We thought creating silence could be even more valuable,” Yang says.

Applying an electrical signal to the piezoelectric fiber causes it to vibrate, which generates sound. The researchers demonstrated this by playing Bach’s “Air” using a 130-micrometer sheet of silk mounted on a circular frame.

To enable direct sound suppression, the researchers use a silk fabric loudspeaker to emit sound waves that destructively interfere with unwanted sound waves. They control the vibrations of the piezoelectric fiber so that sound waves emitted by the fabric are opposite of unwanted sound waves that strike the fabric, which can cancel out the noise.

However, this technique is only effective over a small area. So, the researchers built off this idea to develop a technique that uses fabric vibrations to suppress sound in much larger areas, like a bedroom.

Let’s say your next-door neighbors are playing foosball in the middle of the night. You hear noise in your bedroom because the sound in their apartment causes your shared wall to vibrate, which forms sound waves on your side.

To suppress that sound, the researchers could place the silk fabric onto your side of the shared wall, controlling the vibrations in the fiber to force the fabric to remain still. This vibration-mediated suppression prevents sound from being transmitted through the fabric.

“If we can control those vibrations and stop them from happening, we can stop the noise that is generated, as well,” Yang says.

A mirror for sound

Surprisingly, the researchers found that holding the fabric still causes sound to be reflected by the fabric, resulting in a thin piece of silk that reflects sound like a mirror does with light.

Their experiments also revealed that both the mechanical properties of a fabric and the size of its pores affect the efficiency of sound generation. While silk and muslin have similar mechanical properties, the smaller pore sizes of silk make it a better fabric loudspeaker.

But the effective pore size also depends on the frequency of sound waves. If the frequency is low enough, even a fabric with relatively large pores could function effectively, Yang says.

When they tested the silk fabric in direct suppression mode, the researchers found that it could significantly reduce the volume of sounds up to 65 decibels (about as loud as enthusiastic human conversation). In vibration-mediated suppression mode, the fabric could reduce sound transmission up to 75 percent.

These results were only possible due to a robust group of collaborators, Fink says. Graduate students at the Rhode Island School of Design helped the researchers understand the details of constructing fabrics; scientists at the University of Wisconsin at Madison conducted simulations; researchers at Case Western Reserve University characterized materials; and chemical engineers in the Smith Group at MIT used their expertise in gas membrane separation to measure airflow through the fabric.

Moving forward, the researchers want to explore the use of their fabric to block sound of multiple frequencies. This would likely require complex signal processing and additional electronics.

In addition, they want to further study the architecture of the fabric to see how changing things like the number of piezoelectric fibers, the direction in which they are sewn, or the applied voltages could improve performance.

“There are a lot of knobs we can turn to make this sound-suppressing fabric really effective. We want to get people thinking about controlling structural vibrations to suppress sound. This is just the beginning,” says Yang.

This work is funded, in part, by the National Science Foundation (NSF), the Army Research Office (ARO), the Defense Threat Reduction Agency (DTRA), and the Wisconsin Alumni Research Foundation.

de MIT News https://ift.tt/VDS5J0I

William Green named director of MIT Energy Initiative

MIT professor William H. Green has been named director of the MIT Energy Initiative (MITEI).

In appointing Green, then-MIT Vice President for Research Maria Zuber highlighted his expertise in chemical kinetics — the understanding of the rates of chemical reactions — and the work of his research team in reaction kinetics, quantum chemistry, numerical methods, and fuel chemistry, as well as his work performing techno-economic assessments of proposed fuel and vehicle changes and biofuel production options.

“Bill has been an active participant in MITEI; his broad view of energy science and technology will be a major asset and will position him well to contribute to the success of MIT’s exciting new Climate Project,” Zuber wrote in a letter announcing the appointment, which went into effect April 1. 

Green is the Hoyt C. Hottel Professor of Chemical Engineering and previously served as the executive officer of the MIT Department of Chemical Engineering from 2012 to 2015. He sees MITEI’s role today as bringing together the voices of engineering, science, industry, and policy to quickly drive the global energy transition.

“MITEI has a very important role in fostering the energy and climate innovations happening at MIT and in building broader consensus, first in the engineering community and then ultimately to start the conversations that will lead to public acceptance and societal consensus,” says Green.

Achieving consensus much more quickly is essential, says Green, who noted that it was during the 1992 Rio Summit that globally we recognized the problem of greenhouse gas emissions, yet almost a quarter-century passed before the Paris Agreement came into force. Eight years after the Paris Agreement, there is still disagreement over how to address this challenge in most sectors of the economy, and much work to be done to translate the Paris pledges into reality.

“Many people feel we’re collectively too slow in dealing with the climate problem,” he says. “It’s very important to keep helping the research community be more effective and faster to provide the solutions that society needs, but we also need to work on being faster at reaching consensus around the good solutions we do have, and supporting them so they’ll actually be economically attractive so that investors can feel safe to invest in them, and to change regulations to make them feasible, when needed.”

With experience in industry, policy, and academia, Green is well positioned to facilitate this acceleration. “I can see the situation from the point of view of a scientist, from the point of view of an engineer, from the point of view of the big companies, from the point of view of a startup company, and from the point of view of a parent concerned about the effects of climate change on the world my children are inheriting,” he says.

Green also intends to extend MITEI’s engagement with a broader range of countries, industries, and economic sectors as MITEI focuses on decarbonization and accelerating the much-needed energy transition worldwide.

Green received a PhD in physical chemistry from the University of California at Berkeley and a BA in chemistry from Swarthmore College. He joined MIT in 1997. He is the recipient of the AIChE’s R.H. Wilhelm Award in Chemical Reaction Engineering and is an inaugural Fellow of the Combustion Institute.

He succeeds Robert Stoner, who served as interim director of MITEI beginning in July 2023, when longtime director Robert C. Armstrong retired after serving in the role for a decade.

de MIT News https://ift.tt/371cQwr

Seizing solar’s bright future

Consider the dizzying ascent of solar energy in the United States: In the past decade, solar capacity increased nearly 900 percent, with electricity production eight times greater in 2023 than in 2014. The jump from 2022 to 2023 alone was 51 percent, with a record 32 gigawatts (GW) of solar installations coming online. In the past four years, more solar has been added to the grid than any other form of generation. Installed solar now tops 179 GW, enough to power nearly 33 million homes. The U.S. Department of Energy (DOE) is so bullish on the sun that its decarbonization plans envision solar satisfying 45 percent of the nation’s electricity demands by 2050.

But the continued rapid expansion of solar requires advances in technology, notably to improve the efficiency and durability of solar photovoltaic (PV) materials and manufacturing. That’s where Optigon, a three-year-old MIT spinout company, comes in.

“Our goal is to build tools for research and industry that can accelerate the energy transition,” says Dane deQuilettes, the company’s co-founder and chief science officer. “The technology we have developed for solar will enable measurements and analysis of materials as they are being made both in lab and on the manufacturing line, dramatically speeding up the optimization of PV.”

With roots in MIT’s vibrant solar research community, Optigon is poised for a 2024 rollout of technology it believes will drastically pick up the pace of solar power and other clean energy projects.

Beyond silicon

Silicon, the material mainstay of most PV, is limited by the laws of physics in the efficiencies it can achieve converting photons from the sun into electrical energy. Silicon-based solar cells can theoretically reach power conversion levels of just 30 percent, and real-world efficiency levels hover in the low 20s. But beyond the physical limitations of silicon, there is another issue at play for many researchers and the solar industry in the United States and elsewhere: China dominates the silicon PV market, from supply chains to manufacturing.

Scientists are eagerly pursuing alternative materials, either for enhancing silicon’s solar conversion capacity or for replacing silicon altogether.

In the past decade, a family of crystal-structured semiconductors known as perovskites has risen to the fore as a next-generation PV material candidate. Perovskite devices lend themselves to a novel manufacturing process using printing technology that could circumvent the supply chain juggernaut China has built for silicon. Perovskite solar cells can be stacked on each other or layered atop silicon PV, to achieve higher conversion efficiencies. Because perovskite technology is flexible and lightweight, modules can be used on roofs and other structures that cannot support heavier silicon PV, lowering costs and enabling a wider range of building-integrated solar devices.

But these new materials require testing, both during R&D and then on assembly lines, where missing or defective optical, electrical, or dimensional properties in the nano-sized crystal structures can negatively impact the end product.

“The actual measurement and data analysis processes have been really, really slow, because you have to use a bunch of separate tools that are all very manual,” says Optigon co-founder and chief executive officer Anthony Troupe ’21. “We wanted to come up with tools for automating detection of a material’s properties, for determining whether it could make a good or bad solar cell, and then for optimizing it.”

“Our approach packed several non-contact, optical measurements using different types of light sources and detectors into a single system, which together provide a holistic, cross-sectional view of the material,” says Brandon Motes ’21, ME ’22, co-founder and chief technical officer.

“This breakthrough in achieving millisecond timescales for data collection and analysis means we can take research-quality tools and actually put them on a full production system, getting extremely detailed information about products being built at massive, gigawatt scale in real-time,” says Troupe.

This streamlined system takes measurements “in the snap of the fingers, unlike the traditional tools,” says Joseph Berry, director of the US Manufacturing of Advanced Perovskites Consortium and a senior research scientist at the National Renewable Energy Laboratory. “Optigon’s techniques are high precision and allow high throughput, which means they can be used in a lot of contexts where you want rapid feedback and the ability to develop materials very, very quickly.”

According to Berry, Optigon’s technology may give the solar industry not just better materials, but the ability to pump out high-quality PV products at a brisker clip than is currently possible. “If Optigon is successful in deploying their technology, then we can more rapidly develop the materials that we need, manufacturing with the requisite precision again and again,” he says. “This could lead to the next generation of PV modules at a much, much lower cost.”

Measuring makes the difference

With Small Business Innovation Research funding from DOE to commercialize its products and a grant from the Massachusetts Clean Energy Center, Optigon has settled into a space at the climate technology incubator Greentown Labs in Somerville, Massachusetts. Here, the team is preparing for this spring’s launch of its first commercial product, whose genesis lies in MIT’s GridEdge Solar Research Program.

Led by Vladimir Bulović, a professor of electrical engineering and the director of MIT.nano, the GridEdge program was established with funding from the Tata Trusts to develop lightweight, flexible, and inexpensive solar cells for distribution to rural communities around the globe. When deQuilettes joined the group in 2017 as a postdoc, he was tasked with directing the program and building the infrastructure to study and make perovskite solar modules.

“We were trying to understand once we made the material whether or not it was good,” he recalls. “There were no good commercial metrology [the science of measurements] tools for materials beyond silicon, so we started to build our own.” Recognizing the group’s need for greater expertise on the problem, especially in the areas of electrical, software, and mechanical engineering, deQuilettes put a call out for undergraduate researchers to help build metrology tools for new solar materials.

“Forty people inquired, but when I met Brandon and Anthony, something clicked; it was clear we had a complementary skill set,” says deQuilettes. “We started working together, with Anthony coming up with beautiful designs to integrate multiple measurements, and Brandon creating boards to control all of the hardware, including different types of lasers. We started filing multiple patents and that was when we saw it all coming together.”

“We knew from the start that metrology could vastly improve not just materials, but production yields,” says Troupe. Adds deQuilettes, “Our goal was getting to the highest performance orders of magnitude faster than it would ordinarily take, so we developed tools that would not just be useful for research labs but for manufacturing lines to give live feedback on quality.”

The device Optigon designed for industry is the size of a football, “with sensor packages crammed into a tiny form factor, taking measurements as material flows directly underneath,” says Motes. “We have also thought carefully about ways to make interaction with this tool as seamless and, dare I say, as enjoyable as possible, streaming data to both a dashboard an operator can watch and to a custom database.”

Photovoltaics is just the start

The company may have already found its market niche. “A research group paid us to use our in-house prototype because they have such a burning need to get these sorts of measurements,” says Troupe, and according to Motes, “Potential customers ask us if they can buy the system now.” deQuilettes says, “Our hope is that we become the de facto company for doing any sort of characterization metrology in the United States and beyond.”

Challenges lie ahead for Optigon: product launches, full-scale manufacturing, technical assistance, and sales. Greentown Labs offers support, as does MIT’s own rich community of solar researchers and entrepreneurs. But the founders are already thinking about next phases.

“We are not limiting ourselves to the photovoltaics area,” says deQuilettes. “We’re planning on working in other clean energy materials such as batteries and fuel cells.”

That’s because the team wants to make the maximum impact on the climate challenge. “We’ve thought a lot about the potential our tools will have on reducing carbon emissions, and we’ve done a really in-depth analysis looking at how our system can increase production yields of solar panels and other energy technologies, reducing materials and energy wasted in conventional optimization,” deQuilettes says. “If we look across all these sectors, we can expect to offset about 1,000 million metric tons of CO₂ [carbon dioxide] per year in the not-too-distant future.”

The team has written scale into its business plan. “We want to be the key enabler for bringing these new energy technologies to market,” says Motes. “We envision being deployed on every manufacturing line making these types of materials. It’s our goal to walk around and know that if we see a solar panel deployed, there’s a pretty high likelihood that it will be one we measured at some point.”

de MIT News https://ift.tt/R2vl5JD

President Sally Kornbluth and OpenAI CEO Sam Altman discuss the future of AI

How is the field of artificial intelligence evolving and what does it mean for the future of work, education, and humanity? MIT President Sally Kornbluth and OpenAI CEO Sam Altman covered all that and more in a wide-ranging discussion on MIT’s campus May 2.

The success of OpenAI’s ChatGPT large language models has helped spur a wave of investment and innovation in the field of artificial intelligence. ChatGPT-3.5 became the fastest-growing consumer software application in history after its release at the end of 2022, with hundreds of millions of people using the tool. Since then, OpenAI has also demonstrated AI-driven image-, audio-, and video-generation products and partnered with Microsoft.

The event, which took place in a packed Kresge Auditorium, captured the excitement of the moment around AI, with an eye toward what’s next.

“I think most of us remember the first time we saw ChatGPT and were like, ‘Oh my god, that is so cool!’” Kornbluth said. “Now we’re trying to figure out what the next generation of all this is going to be.”

For his part, Altman welcomes the high expectations around his company and the field of artificial intelligence more broadly.

“I think it’s awesome that for two weeks, everybody was freaking out about ChatGPT-4, and then by the third week, everyone was like, ‘Come on, where’s GPT-5?’” Altman said. “I think that says something legitimately great about human expectation and striving and why we all have to [be working to] make things better.”

The problems with AI

Early on in their discussion, Kornbluth and Altman discussed the many ethical dilemmas posed by AI.

“I think we’ve made surprisingly good progress around how to align a system around a set of values,” Altman said. “As much as people like to say ‘You can’t use these things because they’re spewing toxic waste all the time,’ GPT-4 behaves kind of the way you want it to, and we’re able to get it to follow a given set of values, not perfectly well, but better than I expected by this point.”

Altman also pointed out that people don’t agree on exactly how an AI system should behave in many situations, complicating efforts to create a universal code of conduct.

“How do we decide what values a system should have?” Altman asked. “How do we decide what a system should do? How much does society define boundaries versus trusting the user with these tools? Not everyone will use them the way we like, but that’s just kind of the case with tools. I think it’s important to give people a lot of control … but there are some things a system just shouldn’t do, and we’ll have to collectively negotiate what those are.”

Kornbluth agreed doing things like eradicating bias in AI systems will be difficult.

“It’s interesting to think about whether or not we can make models less biased than we are as human beings,” she said.

Kornbluth also brought up privacy concerns associated with the vast amounts of data needed to train today’s large language models. Altman said society has been grappling with those concerns since the dawn of the internet, but AI is making such considerations more complex and higher-stakes. He also sees entirely new questions raised by the prospect of powerful AI systems.

“How are we going to navigate the privacy versus utility versus safety tradeoffs?” Altman asked. “Where we all individually decide to set those tradeoffs, and the advantages that will be possible if someone lets the system be trained on their entire life, is a new thing for society to navigate. I don’t know what the answers will be.”

For both privacy and energy consumption concerns surrounding AI, Altman said he believes progress in future versions of AI models will help.

"What we want out of GPT-5 or 6 or whatever is for it to be the best reasoning engine possible,” Altman said. “It is true that right now, the only way we’re able to do that is by training it on tons and tons of data. In that process, it’s learning something about how to do very, very limited reasoning or cognition or whatever you want to call it. But the fact that it can memorize data, or the fact that it’s storing data at all in its parameter space, I think we'll look back and say, ‘That was kind of a weird waste of resources.’ I assume at some point, we’ll figure out how to separate the reasoning engine from the need for tons of data or storing the data in [the model], and be able to treat them as separate things.”

Kornbluth also asked about how AI might lead to job displacement.

“One of the things that annoys me most about people who work on AI is when they stand up with a straight face and say, ‘This will never cause any job elimination. This is just an additive thing. This is just all going to be great,’” Altman said. “This is going to eliminate a lot of current jobs, and this is going to change the way that a lot of current jobs function, and this is going to create entirely new jobs. That always happens with technology."

The promise of AI

Altman believes progress in AI will make grappling with all of the field’s current problems worth it.

“If we spent 1 percent of the world’s electricity training a powerful AI, and that AI helped us figure out how to get to non-carbon-based energy or make deep carbon capture better, that would be a massive win,” Altman said.

He also said the application of AI he’s most interested in is scientific discovery.

“I believe [scientific discovery] is the core engine of human progress and that it is the only way we drive sustainable economic growth,” Altman said. “People aren’t content with GPT-4. They want things to get better. Everyone wants life more and better and faster, and science is how we get there.”

Kornbluth also asked Altman for his advice for students thinking about their careers. He urged students not to limit themselves.

“The most important lesson to learn early on in your career is that you can kind of figure anything out, and no one has all of the answers when they start out,” Altman said. “You just sort of stumble your way through, have a fast iteration speed, and try to drift toward the most interesting problems to you, and be around the most impressive people and have this trust that you’ll successfully iterate to the right thing. ... You can do more than you think, faster than you think.”

The advice was part of a broader message Altman had about staying optimistic and working to create a better future.

“The way we are teaching our young people that the world is totally screwed and that it’s hopeless to try to solve problems, that all we can do is sit in our bedrooms in the dark and think about how awful we are, is a really deeply unproductive streak,” Altman said. “I hope MIT is different than a lot of other college campuses. I assume it is. But you all need to make it part of your life mission to fight against this. Prosperity, abundance, a better life next year, a better life for our children. That is the only path forward. That is the only way to have a functioning society ... and the anti-progress streak, the anti ‘people deserve a great life’ streak, is something I hope you all fight against.”

de MIT News https://ift.tt/C8e7mbK

MIT astronomers observe elusive stellar light surrounding ancient quasars

MIT astronomers have observed the elusive starlight surrounding some of the earliest quasars in the universe. The distant signals, which trace back more than 13 billion years to the universe’s infancy, are revealing clues to how the very first black holes and galaxies evolved.

Quasars are the blazing centers of active galaxies, which host an insatiable supermassive black hole at their core. Most galaxies host a central black hole that may occasionally feast on gas and stellar debris, generating a brief burst of light in the form of a glowing ring as material swirls in toward the black hole.

Quasars, by contrast, can consume enormous amounts of matter over much longer stretches of time, generating an extremely bright and long-lasting ring — so bright, in fact, that quasars are among the most luminous objects in the universe.

Because they are so bright, quasars outshine the rest of the galaxy in which they reside. But the MIT team was able for the first time to observe the much fainter light from stars in the host galaxies of three ancient quasars.

Based on this elusive stellar light, the researchers estimated the mass of each host galaxy, compared to the mass of its central supermassive black hole. They found that for these quasars, the central black holes were much more massive relative to their host galaxies, compared to their modern counterparts.

The findings, published today in the Astrophysical Journal, may shed light on how the earliest supermassive black holes became so massive despite having a relatively short amount of cosmic time in which to grow. In particular, those earliest monster black holes may have sprouted from more massive “seeds” than more modern black holes did.

“After the universe came into existence, there were seed black holes that then consumed material and grew in a very short time,” says study author Minghao Yue, a postdoc in MIT’s Kavli Institute for Astrophysics and Space Research. “One of the big questions is to understand how those monster black holes could grow so big, so fast.”

“These black holes are billions of times more massive than the sun, at a time when the universe is still in its infancy,” says study author Anna-Christina Eilers, assistant professor of physics at MIT. “Our results imply that in the early universe, supermassive black holes might have gained their mass before their host galaxies did, and the initial black hole seeds could have been more massive than today.”

Eilers’ and Yue’s co-authors include MIT Kavli Director Robert Simcoe, MIT Hubble Fellow and postdoc Rohan Naidu, and collaborators in Switzerland, Austria, Japan, and at North Carolina State University.

Dazzling cores

A quasar’s extreme luminosity has been obvious since astronomers first discovered the objects in the 1960s. They assumed then that the quasar’s light stemmed from a single, star-like “point source.” Scientists designated the objects “quasars,” as a portmanteau of a “quasi-stellar” object. Since those first observations, scientists have realized that quasars are in fact not stellar in origin but emanate from the accretion of intensely powerful and persistent supermassive black holes sitting at the center of galaxies that also host stars, which are much fainter in comparison to their dazzling cores.

It’s been extremely challenging to separate the light from a quasar’s central black hole from the light of the host galaxy’s stars. The task is a bit like discerning a field of fireflies around a central, massive searchlight. But in recent years, astronomers have had a much better chance of doing so with the launch of NASA’s James Webb Space Telescope (JWST), which has been able to peer farther back in time, and with much higher sensitivity and resolution, than any existing observatory.

In their new study, Yue and Eilers used dedicated time on JWST to observe six known, ancient quasars, intermittently from the fall of 2022 through the following spring. In total, the team collected more than 120 hours of observations of the six distant objects.

“The quasar outshines its host galaxy by orders of magnitude. And previous images were not sharp enough to distinguish what the host galaxy with all its stars looks like,” Yue says. “Now for the first time, we are able to reveal the light from these stars by very carefully modeling JWST’s much sharper images of those quasars.”

A light balance

The team took stock of the imaging data collected by JWST of each of the six distant quasars, which they estimated to be about 13 billion years old. That data included measurements of each quasar’s light in different wavelengths. The researchers fed that data into a model of how much of that light likely comes from a compact “point source,” such as a central black hole’s accretion disk, versus a more diffuse source, such as light from the host galaxy’s surrounding, scattered stars.

Through this modeling, the team teased apart each quasar’s light into two components: light from the central black hole’s luminous disk and light from the host galaxy’s more diffuse stars. The amount of light from both sources is a reflection of their total mass. The researchers estimate that for these quasars, the ratio between the mass of the central black hole and the mass of the host galaxy was about 1:10. This, they realized, was in stark contrast to today’s mass balance of 1:1,000, in which more recently formed black holes are much less massive compared to their host galaxies.

“This tells us something about what grows first: Is it the black hole that grows first, and then the galaxy catches up? Or is the galaxy and its stars that first grow, and they dominate and regulate the black hole’s growth?” Eilers explains. “We see that black holes in the early universe seem to be growing faster than their host galaxies. That is tentative evidence that the initial black hole seeds could have been more massive back then.”

“There must have been some mechanism to make a black hole gain their mass earlier than their host galaxy in those first billion years,” Yue adds. “It’s kind of the first evidence we see for this, which is exciting.”

de MIT News https://ift.tt/ISK2wUp

Exploring frontiers of mechanical engineering

From cutting-edge robotics, design, and bioengineering to sustainable energy solutions, ocean engineering, nanotechnology, and innovative materials science, MechE students and their advisors are doing incredibly innovative work. The graduate students highlighted here represent a snapshot of the great work in progress this spring across the Department of Mechanical Engineering, and demonstrate the ways the future of this field is as limitless as the imaginations of its practitioners.

Democratizing design through AI

Lyle Regenwetter
Hometown: Champaign, Illinois
Advisor: Assistant Professor Faez Ahmed
Interests: Food, climbing, skiing, soccer, tennis, cooking

Lyle Regenwetter finds excitement in the prospect of generative AI to "democratize" design and enable inexperienced designers to tackle complex design problems. His research explores new training methods through which generative AI models can be taught to implicitly obey design constraints and synthesize higher-performing designs. Knowing that prospective designers often have an intimate knowledge of the needs of users, but may otherwise lack the technical training to create solutions, Regenwetter also develops human-AI collaborative tools that allow AI models to interact and support designers in popular CAD software and real design problems. 

Solving a whale of a problem 

Loïcka Baille
Hometown: L’Escale, France
Advisor: Daniel Zitterbart
Interests: Being outdoors — scuba diving, spelunking, or climbing. Sailing on the Charles River, martial arts classes, and playing volleyball

Loïcka Baille’s research focuses on developing remote sensing technologies to study and protect marine life. Her main project revolves around improving onboard whale detection technology to prevent vessel strikes, with a special focus on protecting North Atlantic right whales. Baille is also involved in an ongoing study of Emperor penguins. Her team visits Antarctica annually to tag penguins and gather data to enhance their understanding of penguin population dynamics and draw conclusions regarding the overall health of the ecosystem.

Water, water anywhere

Carlos Díaz-Marín
Hometown: San José, Costa Rica
Advisor: Professor Gang Chen | Former Advisor: Professor Evelyn Wang
Interests: New England hiking, biking, and dancing

Carlos Díaz-Marín designs and synthesizes inexpensive salt-polymer materials that can capture large amounts of humidity from the air. He aims to change the way we generate potable water from the air, even in arid conditions. In addition to water generation, these salt-polymer materials can also be used as thermal batteries, capable of storing and reusing heat. Beyond the scientific applications, Díaz-Marín is excited to continue doing research that can have big social impacts, and that finds and explains new physical phenomena. As a LatinX person, Díaz-Marín is also driven to help increase diversity in STEM.

Scalable fabrication of nano-architected materials

Somayajulu Dhulipala
Hometown: Hyderabad, India
Advisor: Assistant Professor Carlos Portela
Interests: Space exploration, taekwondo, meditation.

Somayajulu Dhulipala works on developing lightweight materials with tunable mechanical properties. He is currently working on methods for the scalable fabrication of nano-architected materials and predicting their mechanical properties. The ability to fine-tune the mechanical properties of specific materials brings versatility and adaptability, making these materials suitable for a wide range of applications across multiple industries. While the research applications are quite diverse, Dhulipala is passionate about making space habitable for humanity, a crucial step toward becoming a spacefaring civilization.

Ingestible health-care devices

Jimmy McRae
Hometown: Woburn, Massachusetts
Advisor: Associate Professor Giovani Traverso
Interests: Anything basketball-related: playing, watching, going to games, organizing hometown tournaments 

Jimmy McRae aims to drastically improve diagnostic and therapeutic capabilities through noninvasive health-care technologies. His research focuses on leveraging materials, mechanics, embedded systems, and microfabrication to develop novel ingestible electronic and mechatronic devices. This ranges from ingestible electroceutical capsules that modulate hunger-regulating hormones to devices capable of continuous ultralong monitoring and remotely triggerable actuations from within the stomach. The principles that guide McRae’s work to develop devices that function in extreme environments can be applied far beyond the gastrointestinal tract, with applications for outer space, the ocean, and more.

Freestyle BMX meets machine learning

Eva Nates
Hometown: Narberth, Pennsylvania 
Advisor: Professor Peko Hosoi
Interests: Rowing, running, biking, hiking, baking

Eva Nates is working with the Australian Cycling Team to create a tool to classify Bicycle Motocross Freestyle (BMX FS) tricks. She uses a singular value decomposition method to conduct a principal component analysis of the time-dependent point-tracking data of an athlete and their bike during a run to classify each trick. The 2024 Olympic team hopes to incorporate this tool in their training workflow, and Nates worked alongside the team at their facilities on the Gold Coast of Australia during MIT’s Independent Activities Period in January.

Augmenting Astronauts with Wearable Limbs 

Erik Ballesteros
Hometown: Spring, Texas
Advisor: Professor Harry Asada
Interests: Cosplay, Star Wars, Lego bricks

Erik Ballesteros’s research seeks to support astronauts who are conducting planetary extravehicular activities through the use of supernumerary robotic limbs (SuperLimbs). His work is tailored toward design and control manifestation to assist astronauts with post-fall recovery, human-leader/robot-follower quadruped locomotion, and coordinated manipulation between the SuperLimbs and the astronaut to perform tasks like excavation and sample handling.

This article appeared in the Spring 2024 edition of the Department of Mechanical Engineering's magazine, MechE Connects. 

de MIT News https://ift.tt/kxRG21K

President Mokgweetsi Masisi of Botswana visits the Legatum Center at MIT

President Mokgweetsi Masisi of Botswana visited the Legatum Center for Development and Entrepreneurship at MIT on Tuesday, delivering a speech on the value of entrepreneurship in growing economies and affirming an interest in working with the center on spurring innovation in his own country.

“Innovation is … not a privilege for the few, but a powerful tool that should be accessible for all,” Masisi said during a speech at the Legatum Center’s “Innovation in Global Growth Markets: Prosperity Through Entrepreneurship” conference, marking the center’s 15th anniversary.

Botswana, Masisi said, should undertake a “deliberate effort to deliver a vibrant innovation ecosystem by increasing investment in science, technology, and innovation, thus creating space for our current and future generations … to thrive and ensure an improved quality of life” in the country.

MIT President Sally A. Kornbluth also spoke at the event, highlighting the ways that the Legatum Center — which is part of the MIT Sloan School of Management — enables innovation-driven economic growth.

The goal, Kornbluth said, is to “help advance innovative ideas that have the potential for real impact and require long-term investment to succeeed; help connect promising entrpreneurs with investors, mentors, and advisors; and provide the resources that are needed to develop, scale, and deploy their solutions.”

Kornbluth also highlighted MIT’s new effort to combat climate change, the Climate Project at MIT. She noted that more than a quarter of MIT faculty have already been working on climate issues but that the new Institute-wide effort can produce “ways to have talented people do more together than they can do alone, so that we can help direct that collective power to deliver climate solutions to the world, in time.”

Georgia Perakis, the John C Head III Dean (Interim) of MIT Sloan, also delivered remarks at the conference, noting that MIT Sloan and the Legatum Center are committed to “educating principled innovation leaders and entrepreneurs who will make a difference and have an impact in the world.” She added, “And I know with the support of everybody here, this is what we are accomplishing.”

In addition to his appearance at the conference, Masisi, along with a delegation of government leaders from Botswana, met directly with Kornbluth, as well as with Dina H. Sherif, executive director of the Legatum Center, and other MIT administrators and faculty members.

In opening remarks at the conference, Sherif observed, “The majority of the world’s growth now comes from what has historically been referred to as the developing world. It is time for us to start recognizing that our time is now. We are not rising. We are here, we are strong, and it is up to us to create the prosperity that we need.”

Sherif added: “Long heralded as a regional reference for good governance and stability, Botswana is now uniquely positioned to become more influential globally and set an example for a rapid transition to a knowledge economy, leading the path for the rest of Africa.”

Masisi has been president of Botswana since 2018. He served as the country’s vice president from 2014 through 2018 and as a member of parliament from 2009 through 2018. The son of a longtime Botswana politican, Edison Masisi, he has a BA from the University of Botswana and an MA from Florida State University.

Botswana has one of the highest per-capita incomes in Africa. The country gained independence from Britain in 1966 and has been a democracy ever since. However, leaders are continuing to examine ways of diversifying the country’s economy.

As such, Botswana and the Legatum Center issued a memorandum of understanding to explore new ways to enhance innovation-driven growth in the country. Elements of the memorandum include establishing a fellowship for African innovation-driven entrepreneurs and student fellows in the mode of the Legatum Center’s fellowships, accelerating the country’s digitalization through uses of artificial intelligence, building an MIT Sandbox program to encourage entrepreneurship within Botswana, participation in the MIT Regional Entrepreneurship Acceleration Program, and possibly other joint activities.

For its part, the Legatum Center also issued a report summarizing its 15 years of impact in global growth markets. The center was initially housed in the MIT School of Architecture and Planning, during which it supported graduate students from all five schools at MIT. It then became part of the MIT Sloan School of Management in 2014.

The Legatum Center’s Student Fellowship supplies MIT students with curriculum, tuition support, advisor networks, and experiential learning opportunities to help drive their venture ideas ahead. So far, the center has provided over $10 million in fellowship funding to 326 fellows. In turn, those Legatum Fellows have created 282 ventures, about three-quarters of which still exist, raising over $1 billion in funding and creating over 17,000 jobs by themselves.

Among the center’s core aspirations has been to “create a home for immensely talented and promising young entrepreneurs,” said Legatum Group CEO Mark Stoleson, during an interview with MIT News between conference panel sessions.

In turn, Stoleson added, those Legatum Fellows will then “hopefully go back to the countries they came from and start businesses, create jobs, and be leaders within the ecosystem of entrepeneurship and prosperity within their countries.”

de MIT News https://ift.tt/qHoLwY1