Martin Brent Halpern, a UC Berkeley professor emeritus of physics known across the world for his contributions to theoretical physics and beloved by Berkeley faculty for his high spirits, died Jan. 21 at age 78.

Regarded as a brilliant physicist with a vibrant presence on campus, Halpern died in Tucson, Arizona, leaving behind fond memories from his colleagues and an extensive list of accomplishments.

“He loved people,” said Yasunori Nomura, director of the Berkeley Center for Theoretical Physics. Nomura described Halpern as “energetic” and “talkative.”

Nomura met Halpern as a junior faculty member. They were typically the last ones in the office and found themselves chatting — sometimes about physics, sometimes not. Talking “loudly and proudly,” Halpern connected with the people in his department through his energetic nature, according to Nomura.

After retiring from UC Berkeley in 2012, Halpern moved to Tucson, Arizona, his childhood hometown. He made frequent visits to Berkeley, where he had worked for 40 years.

As a mentor and professor, Halpern cared about his students, according to his friend Ori Ganor, a campus associate professor of physics. Ganor regarded Halpern as a colleague, friend and mentor.

“Most advisers would be good if they’d meet a couple times a week. He met with his students every day,” Ganor said. “He had a very strong, theatrical presence in his classes. He could explain difficult topics very clearly for students.”

Among his many passions, physics remained Halpern’s focus throughout his life. His fascination with the sciences stemmed from a young age. In 1956, he was a finalist chosen to attend and compete in the Science Talent Institute week in Washington, D.C., where he was one of two representatives from his home state of Arizona.

In college, as Halpern began asking his professors more fundamental questions, his professors directed the math and chemistry major to the physics department. The once pre-med student ventured to Harvard University, where he received his master’s and doctorate degrees in physics.

After finishing his postdoctoral work at UC Berkeley from 1965 to 1966, Halpern returned as an assistant professor in 1972 and worked his way up to full professor until he retired in 2012.

Halpern collected many honors in his lifetime, including a NATO fellowship at the European Organization for Nuclear Research in Geneva, Switzerland and an invitation from J. Robert Oppenheimer to be a fellow at Princeton University.

Halpern’s colleagues note his contributions in many fields, but he was perhaps most notable in quantum field theory and string theory. He kept working on these topics even after his retirement, according to Ganor.

“He was a person with multiple interests way beyond physics,” Ganor said. “He was not only a brilliant person but also had a great sense of humor, and I could learn a lot talking to him about almost any topic.”