News Archives

Pupa Gilbert earns undergraduate mentoring award

Congrats to Prof. Pupa Gilbert on earning an Award for Mentoring Undergraduates in Research, Scholarly and Creative Activities!

The Office of the Provost offers awards to recognize the important role mentors play in fostering undergraduates’ intellectual, personal and professional growth through participation in high-impact practices including research, scholarly and creative endeavors. These awards provide mentors with recognition for their excellence in mentoring undergraduates and their contribution to our students’ Wisconsin Experience.

Gilbert has mentored many undergraduate and graduate students as a physics professor at UW–Madison. Some of these students, like Andrii Hopanchuk ‘24, worked on individual research projects and served as an undergraduate teaching assistant for her popular course, Physics 109, Physics in the Arts.

“Pupa has supported me in exploring my own work, which ultimately culminated in me single-authoring a paper and publishing it in a peer-reviewed journal,” Hopanchuk wrote in his nomination letter. “Another way Pupa has impacted my professional growth was by maintaining a high standard for me (I wish more people did that).”

In 2020, when in-person undergraduate student research positions were almost non-existent, Gilbert had an idea to hire over a dozen students, largely from the Mercile J. Lee Scholars program, to conduct remote analysis on complicated data sets. Machine learning models are only as good as the data they are trained on, and Gilbert reasoned that a large group of diverse students conducting parallel analyses would yield conclusions that computers never could.

This group of 15 students, dubbed the Cnidarians (from the phylum that includes corals, anemones, and jellyfish — animals these students analyzed in Gilbert’s group), each processed the data, making 11 distinct decisions along the way. At weekly Zoom meetings, results were compared. If the majority of Cnidarians agreed on a solution, it was likely the correct one; if not, the students walked others through the process of how they made the decisions they did.

“We (the Cnidarians, really!) discovered many ways to improve data processing,” Gilbert wrote in a Springer Nature “Behind the Paper” feature. “Diversity is our strength. The accuracy, precision, and overall quality of the results is outstanding and unprecedented.”

Many Cnidarians were among Gilbert’s nominators for the Mentoring award.

“Pupa is one of the few professors I have experienced whose energy for learning is contagious – any student under her mentorship is bound for success,” wrote Virginia Quach ’23, now a Pharmacy doctoral student.

Isabelle LeCloux is a senior chemical engineering major who worked with Gilbert both at UW–Madison and at Lawrence Berkeley National Lab this past summer. She wrote:

“Working with other undergraduates in the welcoming and encouraging environment fostered by Professor Gilbert has allowed me to explore topics that I otherwise would not have been exposed to in my curriculum. Her positive attitude makes her a delight to work with and I always feel that I can ask any questions I may have regarding our work in the group.”

Biology major CP Breit joined the Cnidarians after they had already been working together for a year, but she said that Gilbert made it easy to join the already-established team.

Breit wrote: “During this training period Dr. Gilbert was incredibly supportive and really gaveme the confidence to start processing data quickly. There were certainly shortcomings in my technical acumen but Dr. Gilbert was always positive and encouraging, allowing me to make mistakes, learn how to correct them, and improve.”

All the Cnidarians were named as co-authors on the Gilbert group’s most recent paper, published in February in the prestigious journal Nature Communications. Other Cnidarians co-authored a 2022 JACS paper.

Gilbert and other mentoring awardees were recognized at the Mentor Awards Ceremony held during the annual Undergraduate Research Symposium on April 25.

a group of people stand on a stage, all holding framed certificates
The 2024 Mentor award winners at the Undergraduate Research Symposium. Pupa Gilbert is in the front row, third from right (photo provided by Pupa Gilbert)

Physics students inducted into Phi Beta Kappa

This post is modified from one originally published by University Communications

On Saturday, April 13, physics students Will Cerne and William Griffin were among the 168 University of Wisconsin–Madison Letters & Science undergraduates inducted to the Phi Beta Kappa (ΦΒΚ) academic society. The induction ceremony was held at Varsity Hall in Union South with 350 attending.

In addition to the induction of new undergraduate members, the ceremony also honored four individuals for their contributions to UW–Madison, including Jimena González, a member of the UW–Madison chapter of the Edward A. Bouchet Society and a PhD candidate in Physics (observational cosmology). González accepted one of ΦΒΚ’s graduate student induction invitation.

UW–Madison’s ΦΒΚ chapter, founded in 1899, seeks to honor students who rigorously explore the sciences, arts and humanities.

L&S Dean Eric M. Wilcots led the opening procession and welcome. Chapter President David W. Johnson, economics, hosted the celebration’s 125th year of the founding of the UW–Madison chapter of Phi Beta Kappa. Special guest and president of the national Phi Beta Kappa Society Peter Quimby PhD’99 presented the history of ΦΒΚ. ΦΒΚ stands for philosophia biou kubernetes, which translates to “the love of wisdom is the helmsman of life.”

Inductees excel in all areas of study, ranging from physics to anthropology, and they must have a cumulative GPA of 3.80 or above and meet strenuous math, language, and breadth requirements.

A committee of faculty and staff review the student record for nomination into the chapter. Inductees have a love for learning in multiple areas of study at the intermediate and advanced levels, exploring far beyond their major area of study at UW–Madison.

Ellen Zweibel named Hilldale Professor

profile photo of Ellen Zweibel
Ellen Zweibel, W. L. Kraushaar and Hilldale professor of astronomy and physics (Photo by Althea Dotzour / UW–Madison)

Five members of the University of Wisconsin–Madison faculty, including astronomy and physics professor Ellen Zweibel, have received Hilldale Professorships.

Hilldale Professorships are given to faculty members who excel in scholarly activity, have records of outstanding research or creative work, and show promise of continued productivity. Recipients receive a salary increase in addition to funding that may be used for research support and teaching release. Appointments are for five years with the possibility of renewal until the individual leaves the university or retires.

Zweibel’s work in theoretical astrophysicist specializes in plasma astrophysics and focuses on evolution of astrophysical magnetic fields, interstellar astrophysics, star formation, cosmic rays and stellar physics.


Tulika Bose honored with Vilas Distinguished Achievement Professorship

Vilas Distinguished Achievement Professor Tulika Bose

Sixteen professors, including physics professor Tulika Bose, were named to Vilas Distinguished Achievement Professorships, an award recognizing distinguished scholarship as well as standout efforts in teaching and service. The professorship provides five years of flexible funding — two-thirds of which is provided by the Office of the Provost through the generosity of the Vilas trustees and one-third provided by the school or college whose dean nominated the winner. The awards are supported by the estate of professor, U.S. Senator and UW Regent William F. Vilas (1840-1908).

Jim Reardon wins WISCIENCE Lillian Tong Teaching Award

Each year, the University of Wisconsin–Madison recognizes outstanding academic staff members who have excelled in leadership, public service, research and teaching. These exceptional individuals bring the university’s mission to life and ensure that the Wisconsin Idea extends far beyond the campus and the state. Ten employees won awards this year, including Dr. Jim Reardon, Director of Undergraduate Program with the department of physics.

Jim Reardon’s love of running and his excellence as a physics instructor recently came together in the classroom in a big way with Physics 106: The Physics of Sports, a course he developed and now teaches. The new course applies physical principles to competitive sports, helping students better understand athletic performance. It’s proven exceptionally popular, attracting almost 140 students in only its third semester.

action shot of Jim Reardon teaching
Jim Reardon, director of undergraduate program in the Department of Physics at the University of Wisconsin–Madison, is pictured while teaching during a Physics 106 class held in Chamberlin Hall on March 20, 2024. Kaul is one of ten recipients of a 2024 Academic Staff Excellence Award (ASEA). (Photo by Bryce Richter / UW–Madison)

Reardon’s expertise at course development, his mastery at instruction and his exemplary support of teaching assistants have made him indispensable to the Physics Department. As director of the undergraduate program, he implemented standardized assessments in the department’s large introductory courses. This provided a baseline for successful course modifications and allowed nationwide peer assessment comparisons. As the administrator of the teaching assistant program, Reardon expertly matches the strengths of TAs with the needs of the department.

Reardon is no less valued in the classroom. Students routinely give him the highest of marks. Writes one, “I have never seen a professor or teacher work so effectively and patiently to ensure his students understood the information.”

“Jim is unique in his broad and ready grasp of the subject matter combined with a passion for teaching and making sure that ALL students have access to that subject matter.”

— Sharon Kahn, graduate program manager, Department of Physics

Bringing the Quantum to the Classical: A Hybrid Simulation of Supernova Neutrinos

By Daniel Heimsoth, Physics PhD student

Simulating quantum systems on classical computers is currently a near-impossible task, as memory and computation time requirements scale exponentially with the size of the system. Quantum computers promise to solve this scalability issue, but there is just one problem: they can’t reliably do that right now because of exorbitant amounts of noise. 

So when UW–Madison physics postdoc Pooja Siwach, former undergrad Katie Harrison BS ‘23, and professor Baha Balantekin wanted to simulate neutrino evolution inside a supernova, they needed to get creative.  

profile photo of Pooja Siwach
Pooja Siwach

Their focus was on a phenomenon called collective neutrino oscillations, which describes a peculiar type of interaction between neutrinos. Neutrinos are unique among elementary particles in that they change type, or flavor, as they propagate through space. These oscillations between flavors are dictated by the density of neutrinos and other matter in the medium, both of which change from the core to the outer layers of a supernova. Physicists are interested in how the flavor composition of neutrinos evolve in time; this is calculated using a time evolution simulation, one of the most popular calculations currently done on quantum computers.  

Ideally, researchers could calculate each interaction between every possible pair of neutrinos in the system. However, supernovae produce around 10^58 neutrinos, a literally astronomical number. “It’s really complex, it’s very hard to solve on classical computers,” Siwach says. “That’s why we are interested in quantum computing because quantum computers are a natural way to map such problems.” 

profile photo of Katie Harrison
Katie Harrison

This naturalness is due to the “two-level” similarities between quantum computers and neutrino flavors. Qubits are composed of two-level states, and neutrino flavor states are approximated as two levels in most physical systems including supernovae.  

In a paper published in Physical Review D in October, Siwach, Harrison, and Balantekin studied the collective oscillation problem using a quantum-assisted simulator, or QAS, which combines the benefits of the natural mapping of the system onto qubits and classical computers’ strength in solving matrix equations. 

In QAS, the interactions between particles are broken down into a linear combination of products of Pauli matrices, which are the building blocks for quantum computing operations, while the state itself is split into a sum of simpler states. The quantum portion of the problem then boils down to computing products of basis states with each Pauli term in the interaction. These products are then inputted into the oscillation equations.

a graph with 4 neutrino traces in 4 colors
Flavor composition (y-axis) of four supernova neutrinos over time due to collective oscillations, calculated using the quantum-assisted simulator. The change in flavor for each neutrino over time shows the effect of neutrino-neutrino interactions.

“Then we get the linear-algebraic equations to solve, and solving such equations on a quantum computer requires a lot of resources,” explains Siwach. “That part we do on classical computers.”  

This approach allows researchers to use the quantum computers only once before the actual time evolution simulation is done on a classical computer, avoiding common pitfalls in quantum calculations such as error accumulation over the length of the simulation due to noisy gates. The authors showed that the QAS results for a four-neutrino system match with a pure classical calculation, showcasing the power of this approach, especially compared to a purely quantum simulation which quickly deviates from the exact solution due to accumulated errors from gates controlling two qubits at the same time. 

Still, as with any current application of quantum computers, there are limitations. “There’s only so much information that we can compute in a reasonable amount of time [on quantum computers],” says Siwach. She also laments the scalability of both the QAS and full quantum simulation. “One more hurdle is scaling to a larger number of neutrinos. If we scale to five or six neutrinos, it will require more qubits and more time, because we have to reduce the time step as well.” 

Harrison, who was an undergraduate physics student at UW–Madison during this project, was supported by a fellowship from the Open Quantum Initiative, a new program to expand undergrad research experiences in quantum computing and quantum information science. She enjoyed her time in the program and thinks that it benefits students looking to get involved in research in the field: “I think it’s really good for students to see what it really means to do research and to see if it’s something that you’re capable of doing or something that you’re interested in.” 

trace of neutrino flavor composition over time comparing a quantum simulation to a full classical one
Flavor composition of a neutrino over time using a full quantum simulation (red points) compared to exact solution (black line). The points start to drift from the exact solution after only a few oscillations, highlighting how noise in the quantum computer negatively affects the calculation.


Vernon Barger elected AAAS Fellow

This story is modified from one published by University Communications 

profile photo of Vernon Barger
Vernon Barger

Eight University of Wisconsin­–Madison scholars — including physics professor Vernon Barger — have been elected fellows of the American Association for the Advancement of Science, the world’s largest general scientific society.

Barger was elected for “seminal work in studying fundamental particles at colliders and leadership in particle phenomenology, where theory meets experiment.”

This year, 502 scientists, engineers and innovators were chosen from the AAAS membership to be AAAS Fellows. The honor, presented annually since 1874, recognizes efforts to advance science and society, with the fellows chosen to reflect the highest standards of scientific integrity and professional ethics.

“As we celebrate the 150th anniversary of the AAAS Fellows, AAAS is proud to recognize the newly elected individuals,” said Sudip S. Parikh, AAAS chief executive officer and executive publisher of the Science family of journals. “This year’s class embodies scientific excellence, fosters trust in science throughout the communities they serve and leads the next generation of scientists while advancing scientific achievements.”

The new class of fellows will be featured in the April issue of the journal Science, and each new fellow will be celebrated at a September event in Washington, D.C.

Physics major Nathan Wagner awarded Goldwater Scholarship

This story is modified from one published by University Communications

Physics and mathematics major Nathan Wagner is one of four UW–Madison students named as winners of 2024 Goldwater Scholarships, the premier undergraduate scholarship in mathematics, engineering and the natural sciences in the United States.

The scholarship program honors the late Sen. Barry Goldwater and is designed to foster and encourage outstanding students to pursue research careers.

“I’m so proud of these four immensely talented scholars and all they’ve accomplished,” says Julie Stubbs, director of UW’s Office of Undergraduate Academic Awards. “Their success also reflects well on a campus culture that prioritizes hands-on research experiences for our undergraduates and provides strong mentoring in mathematics, engineering and the natural sciences.”

The other UW–Madison students are juniors Katarina Aranguiz and Scott Chang and sophomore Max Khanov .

A Goldwater Scholarship provides as much as $7,500 each year for up to two years of undergraduate study. A total of 438 Goldwater Scholars were selected this year from a field of 1,353 students nominated by their academic institutions.

profile picture of Nathan Wagner
Nathan Wagner (Photo by Taylor Wolfram / UW–Madison)

Sophomore Nathan Wagner of Madison, Wisconsin

Wagner is majoring in physics and mathematics. Wagner began research in Professor Mark Saffman’s quantum computing lab in spring 2021 as a high school junior. His first-author manuscript, “Benchmarking a Neutral-Atom Quantum Computer” was recently accepted for publication in the International Journal of Quantum Information. In Summer 2023, Wagner started research with the Physics Department’s High Energy Physics Group, working alongside Professor Sridhara Dasu and others on future particle colliders design research. Wagner was invited to present his research at the Department of Physics Board of Visitors meeting in fall 2023. This summer, he will complete a research internship at Argonne National Laboratory near Chicago, focusing on computational physics. Wagner plans to pursue a PhD in physics and a career at a U.S. Department of Energy national laboratory researching novel carbon-neutral energy generation, quantum computing and networking, nuclear photonics and computational physics.

About the Goldwater Scholarship

Congress established the Barry Goldwater Scholarship and Excellence in Education Foundation in 1986. Goldwater served in the U.S. Senate for over 30 years and challenged Lyndon B. Johnson for the presidency in 1964. A list of past winners from UW–Madison can be found here.

Three physics students earn 2024 NSF GRFP awards, four students earn honorable mention

Congrats to Physics PhD student Joyce Lin and undergraduates Brooke Kotten and Lucy Steffes on being awarded the 2024 NSF GRFP! PhD students Owen Eskandari, Sam Kramer, Tali Oh, and Julia Sheffler were awarded Honorable Mentions.

The National Science Foundation (NSF) recently announced the 2024 awards in its Graduate Research Fellowship Program (GRFP), a prestigious and competitive fellowship that helps support outstanding graduate research across the country.

Of those offered awards, 19 are currently UW–Madison graduate students. Seven current UW–Madison undergraduates were also offered the award for their graduate study. Additionally, 33 UW–Madison students were recognized with honorable mentions from NSF.

UW–Madison strongly encourages senior undergraduates and early-career graduate students to apply to this fellowship.