# Faculty Spotlight: Dick Gross, Professor Emeritus

Dick Gross’ contributions to number theory, algebraic geometry, modular forms, and group representations earned him a MacArthur Fellowship in 1986. In 1987, he received the Cole Prize of the American Mathematical Society alongside Don Zagier and Dorian M. Goldfeld for their work formulating and proving the Gross-Zagier formula, which relates the height of Heegner points with the central derivatives of the zeta function of the corresponding elliptical curves. Gross is a fellow of the American Mathematical Society and the American Academy of Arts and Sciences, as well as a member of the National Academy of Sciences and the American Philosophical Society. But for all his accomplishments and contributions, he is a perfect example of how a career in mathematics is not always a straightforward journey. We spoke with Gross about the winding road that took him from math student to math professor, and his legacy at Harvard.

If you ask Dick Gross, his life as a mathematician was kickstarted by Russia. “I was eight years old when Russia sent up Sputnik,” he recalled. What followed was a huge push in math and science across the U.S. that directly benefited students like Gross who went through a public 15 school system with stellar teachers. He was interested in math by junior high, and involved with state-level math competitions in high school. Nevertheless, his career path wasn’t always a straight, well-paved road.

Gross came to Harvard as an undergraduate student convinced his academic future lay in math. But this belief was shaken after what he described as a disastrous attempt at taking the notoriously difficult Math 55 course his first year. “The other students in the classroom were simply better prepared than I was,” Gross admitted. “They were coming out of the New York City and Chicago school systems, and had much more training.” So he decided to take Math 21 instead, and be a physics major.

At the beginning of his second year however, Gross walked past a classroom in Sever Hall where Andrew Gleason was teaching Math 55. “I thought maybe now that I’d taken Math 21, I could understand Math 55 a little better,” Gross said. “I went in and it was fantastic and beautiful.” He had never seen math presented in such a way. Everything that he had been exposed to up to that point required quick solutions to straightforward problems and Gross, by his own admission, has never been the fastest mathematician. Gleason’s teachings pushed students to think slowly and clearly about math, and try to find the best way to express their conclusions.

“I asked Gleason if I could take Math 55 as a physics concentrator who had passed Math 21,” Gross recalled. “He said, sure you can!” So Gross did. By the end of the course, had found a life-long friend in fellow undergraduate student and eventual Harvard math professor Joe Harris, and officially switched his concentration to mathematics.

The effect Math 55 and Gleason had on Gross’ life and career cannot be understated. “Many times when I finally grasped some small point throughout my math research career, I’d exclaim to myself, oh my god! That’s what Andy was trying to teach us!” Gross said. “Math 55 was this big, fantastic course that you could get as much out of as you were ready to get out at the time. But you’d get even more later down the line.” What he was taught was burned into his head because he had to prepare for the course and take exams, but he didn’t achieve full understanding of the material until he encountered it in his own research.

This is not to say that when Gross graduated in 1971, he jumped straight into the next phase of his math career. Even after four years at Harvard, he lacked any real experience with research mathematics and wasn’t sure he was ready for the rigor and focus graduate school would require of him. Gross accepted a Sheldon fellowship and studied music in Africa and Asia, but quickly found that the more he played as a profession, the less he loved it. He accepted a Marshall Scholarship and studied a combination of history and sociology at Oxford University, but didn’t really enjoy that, either. Then he went on vacation to Italy with a friend, exploring Renaissance artworks through picturesque Tuscan towns.

“I distinctly remember being in Perugia and looking at these fabulous paintings by Pietro Perugino and thinking to myself, see what this guy contributed!” Gross said.

Painting was Perugino’s talent. Gross knew he didn’t have that gift, he didn’t think he had much of a future in music, and he certainly didn’t have a knack for history.

“The only talent I really had was for math,” he said. “So I thought maybe I ought to explore what it would be like to do research math.” He didn’t want his legacy to come across as derivative. Being involved in a truly creative enterprise was deeply important to Gross.

However, while he was able to change his focus at Oxford to math, he had trouble being taken seriously as a graduate student candidate by most institutions where he applied. “I’d been away from college for three years at this point, traveling around Africa and Asia, studying history and sociology, and going to Italy,” Gross said. “When I wrote my application for graduate school, every place turned me down because they didn’t think I was serious.” But Gross was motivated. He wrote about his plight to his old mentor, Gleason, and was able to join Harvard as a special student with the idea that if he did well his first year, he’d be officially accepted into the graduate math program. “I had the advantage over other graduate students in that I had already tried everything else,” Gross recalled. “I was very committed.”

Once again at home in Harvard’s math community, he found a sense of belonging. Knowing he wanted to study number theory, Gross received what he described as “incredible instruction” from mathematicians such as John Tate and Barry Mazur. He graduated in 1978 and— after holding faculty positions at Princeton University and Brown University—returned to Harvard as a tenured professor in 1985. Thus began what amounted to over 30 years of service to the Harvard math community not just in his capacity as professor and researcher, but as department chair, Dean for Undergraduate Education and, ultimately, Dean of Harvard College.

Gross was appointed George Vasmer Leverett Professor in 1998 and department chair in 1999. The latter was his first brush with the more administrative side of Harvard and an unexpected left turn in his career. He was just finishing his chairmanship when William C. Kirby—Dean of the Faculty of Arts and Sciences (FAS) at the time— appointed Gross to lead the first review of undergraduate education in nearly 30 years. “I was very interested because over the years things had evolved into something odd and obsolete,” Gross recalled. “I thought it was a good time for change and Bill needed someone who was familiar with the sciences.”

Gross was Dean for Undergraduate Education from 2002 to 2003 and Dean of Harvard College from 2003 to 2007. In that time, he oversaw a number of programs essential to the undergraduate learning experience, including the academic concentration, the Core Curriculum, the tutorial system, the Freshman Seminar Program, study abroad, undergraduate research, and issues related to pedagogical innovation and improvement. “I had a staff of over 340 people and a budget of $250 million,” he said of his time as Dean of Harvard College. “It was completely beyond anything that I had experienced before, but I really enjoyed it. I spent four-and-a-half years doing it and I got the curriculum review passed, although it took many years off my life. But I felt that someone must have done that for me when I was an undergraduate at Harvard, so now it was my turn to do it for those kids.”

Gross’ old friend and Higgins Professor of Mathematics Joe Harris shared a memory set during those years that he felt illustrates Gross’ impact on our community. “I was walking through Harvard Yard with him,” Harris recalled. “And I was just bowled over to see that virtually all the students we encountered knew him and clearly felt a personal connection to him. It made me appreciate how rare a person he is.” According to Harris, his friend had a light touch that he has rarely seen from others in the position. “He did an absolutely masterful job of it,” Harris said.

At the end of the day, however, Gross was happy to return to the math department as a professor. As rewarding as his other duties had been, his heart had always been in teaching; he was appropriately named a Harvard College Professor in 2011. Gross estimates that over the years he’s had more than 30 graduate students, each more interesting than the next, and each with such a strong background that all he had to do was get out of their way. The undergraduate students he taught were just as impressive. “I met people like Manjul Bhargava and Jacob Lurie,” Gross said. “And they were like sponges. No matter what I could pour out of my head, they absorbed it all.”

He felt that he was at the center of mathematics, training the next generation of world leaders in the field. Gross viewed Harvard as a leader in mathematical innovation and was conscious of his place there as he got older. While there were still a lot of questions that interested him, as the years went on he felt those questions weren’t as fundamental to the advancement of the field of mathematics as they once might have been. Gross had promised himself that he would retire at 65 to make room for younger faculty that would provide students the creative environment he felt they deserved to progress. It was also around this time that his wife, computational biologist Jill Mesirov, received an offer from the University of California San Diego (UCSD).

Gross taught his last class at Harvard in 2015 and, in 2016, the couple moved to San Diego where Mesirov became associate vice chancellor for computational health sciences and Gross taught the occasional graduate course. “When Covid hit, I decided I didn’t want to teach virtually, so I just retired fully,” Gross said. He still “noodles around,” corresponding with people, and writing the occasional paper, but that’s the extent of it. He is happy enough with his legacy of over 30 years at Harvard and can only hope his work has left a lasting impact. “I think the atmosphere of a place outlives the people who work there,” he said. “And it makes the people who come after them better.”