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Physics grad students share hands-on physics, art lessons with local fifth graders

the 4 kits sent home with the students are laid out and opened up, revealing contents like worksheets, laser pointers, mirrors, and lenses
The at-home physics kits featured lessons on light, such as how it functions as both a particle and a wave, and how light changes as it passes through a prism. PHOTO: AEDAN GARDILL

UW–Madison physics grad student Aedan Gardill has been illustrating physics concepts with art for years, such as through his Instagram account, where he shares ink drawings. Earlier this year, he applied for a grant from the Madison Arts Commission to create hidden portraits of women in the physical sciences that could only be revealed by using polarized lenses. He also planned to visit local schools to explain the concept behind his art and help students make their own images based on his technique.

By the time Gardill learned he had been awarded the grant, the pandemic was in full force, and his plans had to change. While he could still present his portraits at the Wisconsin Science Festival, school visits were no longer in the cards.

“With the realization this summer that school was going to most likely be online in the fall, I had to rethink how I was going to use the funding from the grant,” Gardill explains. “And that has morphed into providing at-home, hands-on learning experiences that we’ll lead virtually.”

Hear more from Aedan and a Henderson Elementary School teacher and student he worked with, by reading the full story

Funding for Gardill’s work is provided by a grant from the Madison Arts Commission, with additional funds from the Wisconsin Arts Board, the Optical Society of America, the International Society for Optics and Photonics, and the UW­–Madison Department of Physics, with special thanks to Arts + Literature Laboratory. UW–Madison physics graduate student volunteers include Abby Bishop, Praful Gagrani, Jimena Gonzalez, Ben Harpt, Preston Huft, Brent Mode, Bryan Rubio Perez, Susan Sorensen, and Jessie Thwaites.

Vernon Barger earns 2021 APS Sakurai Prize

profile photo of Vernon Barger
Vernon Barger

University of Wisconsin­–Madison Physics professor Vernon Barger has won the J.J. Sakurai Prize for Theoretical Particle Physics, the American Physical Society announced October 7.

The J.J. Sakurai Prize is considered ­­one of the most prestigious annual prizes in the field of theoretical high energy physics. Barger, who joined the UW­–Madison faculty in 1965, is a world leader in theoretical particle physics where theory meets experiment. He is one of the founders of collider phenomenology as it is practiced today.

“This prize belongs to the hundreds of students, postdocs, faculty and visiting colleagues who entered the portal of UW–Madison to discover the quarks, leptons and bosons of particle physics,” Barger says. “Only at UW–Madison could this research at the interface of theory and experiment so thrive.”

The techniques that Barger helped develop have been crucial in establishing the experimental foundations of the Standard Model of particle physics and in guiding the search for signals of new physics. His contributions have played a key role in many important milestones in particle physics, including the discovery of the W boson in 1985, the top quark in 1995, and the Higgs boson discovery in 2012.

UW–Madison physics professor Lisa Everett and University of Hawaii professor Xerxes Tata, both phenomenologists, co-nominated Barger for the prize.

“We are thrilled that Vernon Barger has been awarded the 2021 J.J. Sakurai Prize, for which we nominated him for his seminal accomplishments and leadership record in collider physics phenomenology over five decades in the field,” Everett says. “The techniques he has pioneered have and continue to be of pivotal importance for elucidating physics signals at particle colliders, and these contributions are only part of a very long and distinguished research career in theoretical particle physics. He is highly deserving of this honor.”

UW–Madison chemistry professor Martin Zanni also won an APS award, the Earle K. Plyler Prize for Molecular Spectroscopy & Dynamics. Read the UW–Madison news piece about both Barger and Zanni’s awards here.

Robert McDermott elected Fellow of the American Physical Society

profile photo of Robert McDermott
Robert McDermott

Congratulations to Prof. Robert McDermott, who was elected a 2020 Fellow of the American Physical Society! He was elected for seminal contributions to quantum computing with superconducting qubits, including elucidating the origins of decoherence mechanisms, and development of new qubit control and readout methods. He was nominated by the Division of Quantum Information.

APS Fellowship is a distinct honor signifying recognition by one’s professional peers for outstanding contributions to physics. Each year, no more than one half of one percent of the Society’s membership is recognized by this honor.

See the full list of 2020 honorees at the APS Fellows archive.

Massive halo finally explains stream of gas swirling around the Milky Way

a starscape showing the milky way in the distance and a rendering of the gases surrounding the large magellenic cloud
The Large and Small Magellanic Clouds as they would appear if the gas around them was visible to the naked eye. | Credits: Scott Lucchini (simulation), Colin Legg (background)

The Large and Small Magellanic Clouds are satellite galaxies of the Milky Way. They are surrounded by a high-velocity gaseous structure called the Magellanic Stream, which consists of gas stripped from both clouds. So far, simulations have been unable to reconcile observations with a complete picture of how the stream was formed. In this Nature week’s issue, numerical simulations carried out at by Scott Lucchini, graduate student at the Physics Department working with Elena D’Onghia, present a model that potentially resolves this conundrum. By embedding the Large Magellanic Cloud in a corona of ionized gas, the researchers were able to simulate the Magellanic Stream accurately and explain its structure. Ellen Zweibel and Chad Bustard are also co-authors of the article.

Read the full UW news story | Read the Nature article

 

WQI team named winners in international quantum research competition

A WQI faculty team was one of 18 winners in the Innovare Advancement Center’s “Million Dollar International Quantum U Tech Accelerator” competition, which awarded a total of $1.35 million last week. The winning teams, including UW­–Madison physics professors Shimon Kolkowitz and Mark Saffman, each earned $75,000 toward their proposed research.

The competition attracted nearly 250 proposals from teams across the world in the areas of quantum timing, sensing, computing and communications, and 36 teams were invited to present at the live virtual event.

Full story

Prof. Brian Rebel promoted to Senior Scientist at Fermilab

Brian Rebel

Yesterday, Fermilab promoted Prof. Brian Rebel to Senior Scientist. He has a joint appointment there, and his new title at Fermilab is the closest equivalent to full professor for which scientific staff are eligible. Congrats, Brian!

Q-NEXT collaboration awarded National Quantum Initiative funding

The University of Wisconsin–Madison solidified its standing as a leader in the field of quantum information science when the U.S. Department of Energy (DOE) and the White House announced the Q-NEXT collaboration as a funded Quantum Information Science Research Center through the National Quantum Initiative Act. The five-year, $115 million collaboration was one of five Centers announced today.

Q-NEXT, a next-generation quantum science and engineering collaboration led by the DOE’s Argonne National Laboratory, brings together nearly 100 world-class researchers from three national laboratories, 10 universities including UW–Madison, and 10 leading U.S. technology companies to develop the science and technology to control and distribute quantum information.

“The main goals for Q-NEXT are first to deliver quantum interconnects — to find ways to quantum mechanically connect distant objects,” says Mark Eriksson, the John Bardeen Professor of Physics at UW–Madison and a Q-NEXT thrust lead. “And next, to establish a national resource to both develop and provide pristine materials for quantum science and technology.”

profile photo of Mark Eriksson
Mark Eriksson

Q-NEXT will focus on three core quantum technologies:

  • Communication for the transmission of quantum information across long distances using quantum repeaters, enabling the establishment of “unhackable” networks for information transfer
  • Sensors that achieve unprecedented sensitivities with transformational applications in physics, materials, and life sciences
  • Processing and utilizing “test beds” both for quantum simulators and future full-stack universal quantum computers with applications in quantum simulations, cryptanalysis, and logistics optimization.

Eriksson is leading the Materials and Integration thrust, one of six Q-NEXT focus areas that features researchers from across the collaboration. This thrust aims to: develop high-coherence materials, including for silicon and superconducting qubits, which is an essential component of preserving entanglement; develop a silicon-based optical quantum memory, which is important in developing a quantum repeater; and improve color-center quantum bits, which are used in both communication and sensing.

“One of the key goals in Materials and Integration is to not just improve the materials but also to improve how you integrate those materials together so that in the end, quantum devices maintain coherence and preserve entanglement,” Eriksson says. “The integration part of the name is really important. You may have a material that on its own is really good at preserving coherence, yet you only make something useful when you integrate materials together.”

Six other UW­–Madison and Wisconsin Quantum Institute faculty members are Q-NEXT investigators: physics professors Victor Brar, Shimon Kolkowitz, Robert McDermott, and Mark Saffman, electrical and computer engineering professor Mikhail Kats, and chemistry professor Randall Goldsmith. UW–Madison researchers are involved in five of the six research thrusts.

“I’m excited about Q-NEXT because of the connections and collaborations it provides to national labs, other universities, and industry partners,” Eriksson says. “When you’re talking about research, it’s those connections that often lead to the breakthroughs.

The potential impacts of Q-NEXT research include the creation of a first-ever National Quantum Devices Database that will promote the development and fabrication of next generation quantum devices as well as the development of the components and systems that enable quantum communications across distances ranging from microns to kilometers.

“This funding helps ensure that the Q-NEXT collaboration will lead the way in future developments in quantum science and engineering,” says Steve Ackerman, UW–Madison vice chancellor for research and graduate education. “Q-NEXT is the epitome of the Wisconsin Idea as we work together to transfer new quantum technologies to the marketplace and support U.S. economic competitiveness in this growing field.”

infographic of all q-next partner national labs, universities, and industry
The Q-NEXT partners

New study expands types of physics, engineering problems that can be solved by quantum computers

A well-known quantum algorithm that is useful in studying and solving problems in quantum physics can be applied to problems in classical physics, according to a new study in the journal Physical Review A from University of Wisconsin–Madison assistant professor of physics Jeff Parker.

Quantum algorithms – a set of calculations that are run on a quantum computer as opposed to a classical computer – used for solving problems in physics have mainly focused on questions in quantum physics. The new applications include a range of problems common to physics and engineering, and expands on the types of questions that can be asked in those fields.

profile photo of Jeff Parker
Jeff Parker

“The reason we like quantum computers is that we think there are quantum algorithms that can solve certain kinds of problems very efficiently in ways that classical computers cannot,” Parker says. “This paper presents a new idea for a type of problem that has not been addressed directly in the literature before, but it can be solved efficiently using these same quantum computer types of algorithms.”

The type of problem Parker was investigating is known as generalized eigenvalue problems, which broadly describe trying to find the fundamental frequencies or modes of a system. Solving them is crucial to understanding common physics and engineering questions, such as the stability of a bridge’s design or, more in line with Parker’s research interests, the stability and efficiency of nuclear fusion reactors.

As the system being studied becomes more and more complex — more components moving throughout three-dimensional space — so does the numerical matrix that describes the problem. A simple eigenvalue problem can be solved with a pencil and paper, but researchers have developed computer algorithms to tackle increasingly complex ones. With the supercomputers available today, more and more difficult physics problems are finding solutions.

“If you want to solve a three-dimensional problem, it can be very complex, with a very complicated geometry,” Parker says. “You can do a lot on today’s supercomputers, but there tends to be a limit. Quantum algorithms may be able to break that limit.”

The specific quantum algorithm that Parker studied in this paper, known as quantum phase estimation, had been previously applied to so-called standard eigenvalue problems. However, no one had shown that they could be applied to the generalized eigenvalue problems that are also common in physics. Generalized eigenvalue problems introduce a second matrix that ups the mathematical complexity.

Parker took the quantum algorithm and extended it to generalized eigenvalue problems. He then looked to see what types of matrices could be used in this problem. If the matrix is sparse ­— meaning, if most of the numerical components that make it up are zero — it means this problem could be solved efficiently on a quantum computer.

The study shows that quantum algorithms could be applied to classical physics problems, such as nuclear fusion mirror machines. | Credit: Cary Forest

“What I showed is that there are certain types of generalized eigenvalue problems that do lead to a sparse matrix and therefore could be efficiently solved on a quantum computer,” Parker says. “This type includes the very natural problems that often occur in physics and engineering, so this study provides motivation for applying these quantum algorithms more to generalized eigenvalue problems, because it hasn’t been a big focus so far.”

Parker emphasizes that quantum computers are in their infancy, and these classical physics problems are still best approached through classical computer algorithms.

“This study provides a step in showing that the application of a quantum algorithm to classical physics problems can be useful in the future, and the main advance here is it shows very clearly another type of problem to which quantum algorithms can be applied,” Parker says.

The study was completed in collaboration with Ilon Joseph at Lawrence Livermore National Laboratory. Funding support was provided by the U.S. Department of Energy to Lawrence Livermore National Laboratory under Contract No. DE-AC52-07NA27344 and U.S. DOE Office of Fusion Energy Sciences “Quantum Leap for Fusion Energy Sciences” (FWP SCW1680).

A somber remembrance marks the 50th anniversary of the Sterling Hall bombing

By Doug Erickson

On an August afternoon 50 years ago, graduate student Bill Evans bumped into Robert Fassnacht, a postdoctoral researcher, in Sterling Hall at the University of Wisconsin­–Madison.

The two didn’t know each other well, but they had talked before. Both were conducting physics experiments in Sterling Hall.

profile photo of Robert Fassnacht
33-year-old Robert Fassnacht, a postdoctoral researcher in physics and father of three young children, was killed in the bombinb. It injured four others. | UW ARCHIVES

Fassnacht mentioned he’d be working through the night. Evans planned to do the same, so he made a mental note to walk over and chat with Fassnacht at some point.

The conversation never happened. At 3:42 a.m. that morning — August 24, 1970 — a bomb tore through a wing of Sterling Hall, killing Fassnacht. Evans, whose lab was much farther from the blast, felt the building shake but was uninjured.

A short time later, Evans says he and another physics researcher, John Lynch, came upon Fassnacht’s lifeless body.

“That’s the part I’m trying to forget and the reason I haven’t talked about it in all these years,” says Evans, 78, by phone from his home in California. “I still have flashbacks.”

The target of the explosion was the Army Mathematics Research Center, housed on multiple upper floors of Sterling Hall. Four young men orchestrated the bombing as a protest against the center’s research connections with the U.S. military during the Vietnam War.

Fassnacht, 33, working in a basement lab in the Physics Department below the Army Mathematics Research Center, was an unintended victim. His research had no connection to the center. Four others — three in Sterling Hall and one across the street at University Hospital — were injured.

black and white photo of Sterling Hall after the bombing shows a building with windows blown out and obvious damage.
The bombing of Sterling Hall on August 24, 1970, was the shocking culmination of years of dissent and despair over the Vietnam War. | UW ARCHIVES

Three of the four bombers — David Fine and brothers Karl and Dwight Armstrong — eventually served prison time. The fourth, Leo Burt, remains at large. Burt and Fine were UW–Madison students at the time.

Evans was pursuing a Ph.D. in atomic physics. He remembers feeling the building shudder, then seeing a wave of dirt and dust blow by a lab door.

He immediately called the university’s overnight phone desk and reported that something terrible had happened at Sterling Hall.

Stepping into the hallway, he tried to head toward the blast’s origin, but thick dust forced him back. He called the UW operator again: “You better get someone over here.”

Evans then went down a basement hallway in the other direction.

“I came upon a night watchman, dazed and covered all over with what looked like pieces of insulation,” he says. “I got him out of the building. There were two policemen nearby, and I yelled, ‘This guy needs help.’”

The night watchman, UW security officer Norbert Sutter, suffered memory impairment, disc problems, and permanent loss of some hearing and vision. The officers who helped Sutter insisted that Evans go with them to University Hospital to be checked for possible injuries. At the time, the hospital was located across Charter Street from Sterling Hall. Evans, certain he was not injured, protested but gave in, then quickly slipped out of the hospital before being evaluated.

Returning to Sterling Hall, Evans says he ran into Lynch. Today, the two differ on the sequence of events that led them to Fassnacht’s body. Both say it’s hard to remember events from so far back — some details remain vivid to them; others have become hazy with time.

The blast had awakened Lynch at his apartment just a few blocks away. He remembers racing to Sterling Hall and entering the building alone. He says he saw Fassnacht’s body, then went looking for others dead or alive inside the building.

“There were no policemen, no firemen yet,” says Lynch, 82, who is retired from the National Science Foundation and lives in Florida. “I’m running around looking for anybody alive. The person I found was Bill Evans.”

Evans thinks he ran into Lynch in the crowd that was forming outside Sterling Hall. He recalls the two of them entering the building together and finding Fassnacht’s body.

“He was face down, with a large piece of concrete on him, and his nose and mouth were under water,” Evans says. “There was no question he was dead. The water (due to broken water pipes) was fairly deep by then.”

The two alerted rescuers to Fassnacht’s body. The pair also helped emergency workers find and shut off a gas leak that had led to a fire, Lynch says.

Later that same day, Lynch recounted the story to a reporter for The Capital Times, the city’s afternoon newspaper. The article’s large headline reads, “I Found Bob Under a Foot of Water.”

Given the era’s anti-war fervor, Lynch says it did not surprise him to look out his bedroom window and see Sterling Hall with a cloud of smoke above it. He had stopped spending evenings at Sterling Hall after a conversation with strangers in a Madison bar a few months earlier.

“One guy said to me, ‘Don’t hang around that place at night. Bad things are going to happen there,’” Lynch says. “I didn’t go to the police because people were saying all sorts of crazy things back then. But I felt I had been forewarned.”

Lynch provided prosecutors with a deposition in the case. Following an esteemed career, he received a Distinguished Alumni Fellow Award in 2003 from UW–Madison’s Physics Department. The department recognized him in large part for his early and sustained support at the federal level of the IceCube Neutrino Observatory, a project at the South Pole managed and operated by UW–Madison.

Evans told his story to law enforcement officers but says he otherwise has rarely discussed his involvement with anyone.

In the spring of 1972, Evans married fellow UW–Madison student Gertrude “Kim” Miller. A few months later, the couple moved to Washington, D.C., where Evans began a job at the U.S. Naval Research Laboratory. He returned to Madison in 1975 to defend his doctoral dissertation but otherwise has not been back to campus.

Evans retired in 2012 following a long career as a research physicist and software architect. He says he’s spent five decades avoiding anything that might trigger a memory of Sterling Hall.

“I tried not to think of it for obvious reasons,” he says. “I guess you could say I disappeared for a good while.”

The experience remains upsetting.

“What happens is it pops up in your memory and then takes about a week to disappear,” Evans says. “I guess it would be like what they talk about with PTSD (post-traumatic stress disorder). If so, I can understand why these people have troubles.”

Late last year, in anticipation of the 50th anniversary of the Sterling Hall bombing this August, UW–Madison issued a call to alumni for memories related to the bombing. Hundreds responded. A sample can be found in the summer 2020 issue of On Wisconsin, the university’s alumni magazine.

Evans was not among those who submitted memories. He says he read the magazine article and found it interesting how the bombing impacted other people. For him, though, it is something he prefers not to reflect on.

“It was so long ago,” he says. “Strange things happen.”

black and white photo of a blown-out building due to bomb damage
Damage as seen from inside the building. | UW ARCHIVES

NSF Physics Frontier Center for neutron star modeling to include UW–Madison

A group of universities, including the University of Wisconsin–Madison, has been named the newest Physics Frontier Center, the National Science Foundation announced Aug. 17. The center expands the reach and depth of existing capabilities in modeling some of the most violent events known in the universe: the mergers of neutron stars and their explosive aftermath.

The Network for Neutrinos, Nuclear Astrophysics, and Symmetries (N3AS) is already an established hub of eight institutions, including UW–Madison, that uses the most extreme environments found in astrophysics — the Big Bang, supernovae, and neutron star and black hole mergers — as laboratories for testing fundamental physics under conditions beyond the reach of Earth-based labs. The upgrade to a Physics Frontier Center adds five institutions, provides $10.9 million in funding for postdoctoral fellowships and allows members to cover an expanded scope of research.

“For 20 years, we’ve expected that the growing precision of astrophysical and cosmological measurements would make this field an increasingly important part of fundamental physics. Indeed, four monumental discoveries — neutrino masses, dark matter, the accelerating universe, and gravitational waves — have confirmed this prediction,” says A. Baha Balantekin, a professor of physics at UW–Madison and one of the principal investigators for N3AS.

Read the full story