UC physicist wins Bessel Award

Particle physicist Jure Zupan is helping us better understand the origins of the universe

University of Cincinnati particle physicist Jure Zupan was awarded a prestigious research award from a German foundation for his theoretical work.

Zupan received the Friedrich Wilhelm Bessel Research Award from the Alexander von Humboldt Foundation in recognition of his lifetime achievement in research on dark matter, antimatter and subatomic particles called quarks.

The theoretical physicist in UC's McMicken College of Arts and Sciences is grappling with a great paradox about the creation of the universe known as the Big Bang: If matter and antimatter were formed in equal parts, how did matter prevail over antimatter?

“The main question we’re addressing is: Why are we here? How is it possible?” he said. “Why did matter dominate over antimatter? It’s a fundamental question of particle physics. We still don’t know the answer.”

The international recognition reflects UC's commitment to research as described in its strategic direction, Next Lives Here.

Jure Zupan stands at a blackboard covered in physics formulas and equations.

UC physics professor Jure Zupan is studying a variety of big questions surrounding the origins of the universe that particle physics might unlock. Photo/Joseph Fuqua II/UC Creative Services

Zupan is originally from Slovenia. He has studied at the University of Haifa in Israel and at particle accelerator labs such as at CERN in Switzerland, among others. He was inspired to pursue physics by reading the works of Carl Sagan and one of his personal heroes, Nobel-winning theoretical physicist and author Steven Weinberg, who wrote about the origins of the universe.

“I remember reading his ‘The First Three Minutes’ in seventh grade,” Zupan said. 

During his career, he has been the sole author of a journal article just once, when he was a student. Particle physics is a particularly collaborative field, he said. Zupan said he didn’t fully appreciate the benefits of collaboration until he went to the Aspen Center for Physics, where scientists work together largely uninterrupted for two or three weeks at a time.

“You’ll have 40 people in the same place. And you have enough time to think through problems,” he said.

The pace of advances can be really glacial, but there have been significant changes to what we know.

Jure Zupan, UC particle physicist

Zupan said he is grateful for the research award.

“It’s a nice acknowledgement that your work is appreciated,” he said. 

Big discoveries get lots of attention, but advances in science more typically come in tiny increments, he said.

“Day to day, it can be hard to appreciate the developments. The pace of advances can be really glacial,” he said. “But there have been significant changes to what we know.”

One landmark event was CERN’s 2012 discovery of an elemental particle called the Higgs boson. This is sometimes called “the God particle,” a phrase author Dick Teresi coined in 1993 with which some physicists, including Zupan, find objectionable.

“It sells books. It has nothing to do with God,” Zupan said.

A colorful image of stars and a gaseous cloud in the Carina Nebula.

University of Cincinnati physicist Jure Zupan is studying dark matter, which is believed to compose a majority of matter in the universe. Here a cloud of interstellar gas billows around the Carina Nebula captured by NASA's Hubble Space Telescope. Photo/NASA Goddard

While Zupan has written numerous papers on Higgs physics, his interests are extensive, his UC research partners say. Last year, Zupan was named a fellow of the American Physical Society for “pioneering contributions” to the fields of flavor physics, dark matter physics and Higgs research.

“He has a broad overview of all the theories out there. That combines to give him a good intuition of what is important and what are the relevant questions,” UC assistant professor Joachim Brod said. “And he is genuinely interested in physics. He wants to understand things.”

A blackboard has various physics equations and formulas in chalk.

UC professor Jure Zupan said physicists are divided into two camps: whiteboard or blackboard enthusiasts. He prefers blackboards but uses a whiteboard at home. Photo/Joseph Fuqua II/UC Creative Services

Brod has collaborated with Zupan on more than a dozen papers, many of them on dark matter physics. Dark matter is believed to make up the vast majority of the universe but has been observed only indirectly through its gravitational effects.

“We are much more certain what dark matter is not than we are what it is,” NASA wrote in its Share the Science explanation.

“We think we are immersed in a sea of dark matter that we just don’t see,” Brod said. “Our approach is to be completely open minded. We don’t know what dark matter is so we assume the most general properties.”

The theorists make predictions based on the observed interactions, he said.

“We know that dark matter has gravitational interactions, but we want to see if it has other interactions as well,” Brod said.

“If you’re working on dark matter, it’s a golden age because there are so many new dark matter experiments coming online,” UC physics professor Alexander Kagan said.

Zupan and Kagan co-authored several papers on a phenomenon called charge-parity symmetry, which tries to explain why the universe has more matter than antimatter. The Large Hadron Collider at CERN is examining this question, among others.

An enormous new particle collider in China could offer clues for Kagan’s area of research. But construction on that could take more than a decade.

“CERN is building one as well. It’s so fabulously expensive that there is only room for one in the world,” Kagan said. “It will be ready to run in about 30 years or so. I have to go the gym to stay in shape.”

Jure Zupan gestures while talking at his desk.

UC physics professor Jure Zupan has written about different fields of particle physics, including Higgs physics, dark matter and flavor physics. Photo/Joseph Fuqua II/UC Creative Services

But Zupan’s curiosity is boundless, leading him to explore a wide range of particle physics questions, Kagan said.

“One of Jure’s great strengths is his breadth. He is involved in everything: flavor physics, Higgs physics, dark matter physics,” Kagan said. “He is an expert in all areas.”

Still, Kagan said many of the questions UC physicists are asking could remain unresolved for lifetimes.

“The life of a theoretical physicist is going from one confusion to the next,” Kagan said. “We’re confused about one thing and go on to another confusion until we get it all worked out. Jure is great at clearing up confusion.”

Zupan said he loves the collaborative spirit of his field. He especially enjoys working with international research partners, he said.

“It adds a lot because their research styles are so different. The way physicists approach a problem in Israel is different from how they approach the same problem in Europe,” he said. “Working with physicists from around the world is a lot of fun.”

Featured image at top: UC physicist Jure Zupan studies particle physics with international collaborators. Photo/Joseph Fuqua II/UC Creative Services

Next Lives Here

The University of Cincinnati is classified as a Research 1 institution by the Carnegie Commission and is ranked in the National Science Foundation's Top-35 public research universities. UC's graduate students and faculty investigate problems and innovate solutions with real-world impact. Next Lives Here.

Become a Bearcat

  • Apply online or get more information about undergraduate enrollment by calling 513-556-1100.
  • Learn more about UC's many undergraduate and graduate programs.