‘Nobel Prize of mathematics’: U of T mathematician Jacob Tsimerman awarded prestigious Fields Medal
Jacob Tsimerman, a professor of mathematics at the University of Toronto, has won the prestigious Fields Medal.
He becomes the first scholar based at a Canadian institution – and the second Canadian – to receive the award, often described as “the Nobel Prize of mathematics,” since it was established in 1932.
The Fields recognizes extraordinary research achievement and the promise of future discoveries. It’s awarded every four years by the International Mathematical Union to up to four mathematicians under the age of 40.
Tsimerman was honoured in part for his role in proving the André-Oort conjecture, a problem that has occupied mathematicians for decades.
“It’s an incredible honour to win this award – not just for me, but for all my collaborators without whom this truly would not be possible,” says Tsimerman, a U of T alumnus. “Math is such a team sport that it becomes impossible to disentangle who contributed what on projects. I’m lucky to have many of my collaborators as close friends, which helps work feel fun and playful.”
The André-Oort conjecture breakthrough
Jacob Tsimerman, right, receives the Fields Medal at the International Congress of Mathematicians in Philadelphia (photo by Allie Ippolito)
Tsimerman found the André-Oort conjecture – or his “mathematical home” as he describes it – during his PhD at Princeton University, where he was advised by number theorist Peter Sarnak.
At a high level, the conjecture concerns the appearance of highly special points inside geometric spaces that encode rich arithmetic information. Mathematicians suspected that whenever these special points appear in large numbers, they do so because they are part of a larger hidden geometric structure.
Tsimerman’s work was crucial in establishing the conjecture and confirming that intuition. The result is significant not only because it solved a long-standing problem, but because it opened entirely new directions of research.
“The Fields Medal recognizes Professor Tsimerman’s tremendous accomplishments and his stature as one of the world’s most promising leaders in mathematical research,” says U of T President Melanie Woodin.
“On behalf of the entire University of Toronto, I want to offer Jacob my heartfelt congratulations. This is a proud and historic moment for all of us.”
Tsimerman’s influence extends well beyond his research. He’s also incredibly popular among U of T students, according to a recent profile in Be Giant.
Professor Mary Pugh, chair of U of T’s department of mathematics, said Tsimerman’s passion for mathematics is evident to anyone who crosses his path.
“I’ve known Jacob as a student and a colleague and, obviously, he is brilliant,” she says. “His love of mathematics is absolutely infectious. He’s someone who can be routinely found in the lounge at a blackboard puzzling over something with a handful of students, delighted to think together with them.”
From math prodigy to Fields Medallist
The 2026 Fields Medal winners, from left: Yu Deng, John Pardon, Jacob Tsimerman and Hong Wang (photo by Allie Ippolito)
Tsimerman’s passion for mathematics began in early childhood.
“By the time I was three, I was enjoying math puzzles,” he says. “My grandfather was a physicist and my mother taught math, so I had a lot of support and resources growing up, along with plenty of puzzles to solve. And that’s what mathematics is, basically: puzzles.”
As a high school student at University of Toronto Schools, Tsimerman won two gold medals at the International Mathematical Olympiad, including a perfect score in 2004. At 16 years old, he started a bachelor’s degree in mathematics at U of T as a member of University College, graduating in just two years in 2006. He earned his PhD from Princeton in 2011.
Tsimerman was a Junior Fellow in Harvard University’s Society of Fellows before joining U of T, where he became the youngest person to be appointed full professor in the department of mathematics in the Faculty of Arts & Science. For the past year, he has served as a distinguished visiting professor in the School of Mathematics at the Institute for Advanced Study in Princeton, N.J.
In addition to the André-Oort conjecture, Tsimerman’s work has influenced areas such as functional transcendence theory, the Ax-Schanuel theorem for Hodge structures and the study of so-called unlikely intersections, where unexpected relationships emerge between geometric and arithmetic objects.
He has also been recognized for resolving the Griffiths conjecture and for developing an o-minimal version of the GAGA theorems – achievements that have deepened connections between geometry, number theory and logic.
“Jacob’s Fields Medal honours his transformative research, which has built connections between disparate fields to capture mathematical structures that had eluded top researchers for decades,” says Professor Robert Jerrard, former chair of U of T’s math department.
“It confirms Jacob’s stature as one of the foremost number theorists of his generation. It also marks a proud moment for our department, where he developed much of his groundbreaking research.”
A growing list of accolades
Jacob Tsimerman stands on stage with his Fields Medal while Robert Jerrard, former chair of U of T’s math department, looks on (photo by Allie Ippolito)
Tsimerman has earned myriad honours throughout his career, including election as a Fellow of both the Royal Society and the Royal Society of Canada in 2025, the Ostrowski Prize in 2023 and the SASTRA Ramanujan Prize in 2015, a world-leading award for young mathematicians.
Tsimerman’s receipt of the Fields Medal reflects U of T’s decades of leadership in mathematical research and education. The award is the namesake of the late John Charles Fields, a celebrated Canadian mathematician who, like Tsimerman, was a U of T alumnus and professor.
U of T also houses the Fields Institute, a world-renowned centre that advances mathematical research in Canada and helps to promote the application of mathematics in modern society.
“It is a thrill to congratulate Professor Tsimerman on receiving this esteemed honour,” says Stephen Wright, dean of U of T’s Faculty of Arts & Science. “The Fields Medal is bestowed in part for future achievements; this is completely consistent with our confidence that Jacob will continue to bring distinction to himself, the department, the faculty and the university.”
