Mathematicians Yu Deng, John Pardon, Jacob Tsimerman and Hong Wang won the 2026 Fields Medal, one of the most coveted awards in their discipline. Their names were revealed today at the International Congress of Mathematicians (ICM) in Philadelphia, Pennsylvania.

The four winners represent a variety of subfields of mathematics, from number theory to mathematical physics. They were all rumored to be favorites to win the medal, which is awarded every four years to up to four mathematicians under the age of 40.

All of the winners work in North America, but two, Deng and Wang, were born and raised in China. They are only the second and third Chinese citizens to have won a Fields Medal: Shing-Tung Yau, now at Tsinghua University in Beijing, won hers in 1982, before Deng or Wang were born. Wang is also the third woman to win the award in the prize’s 90-year history, following the late Maryam Mirzakhani in 2014 and Maryna Viazovska in 2022.

Irreversible fluids

Deng, who is 37 and grew up in Shenzhen, did his doctorate at Princeton University in New Jersey. He is now at the University of Chicago in Illinois, where he specializes in differential equations, which are often used to describe physical phenomena. He says that hearing that he had won the medal made him “very happy, not only for me, but for the field that I represent.”

Deng’s most celebrated achievement was a breakthrough in one of the problems posed by the German mathematician David Hilbert in a landmark talk at the ICM in 1900: he challenged mathematicians to reconcile the smooth behavior and appearance of fluids with the idea (not yet widely accepted at the time) that they were made of multitudes of atoms or molecules.

Together with two collaborators¹Deng found rigorous proof that the microscopic jostling of many constituent particles (acting like small billiard balls continually bouncing off each other) produces as a necessary consequence a differential equation formulated in the late 19th century to describe fluids.

‘Mathematics is an unknown land’: meet Fields Medal winner Maryna Viazovska

This helped reconcile an apparent conundrum. Microscopic physics works just as well when time is reversed, meaning it might be impossible to tell whether a video of two molecules bouncing off each other plays forward or backward. But when many molecules form a fluid, they have an inevitably irreversible behavior: if a cold gas is mixed with a hot one, for example, the mixture will never spontaneously separate into hot and cold.

rope contact

Pardon, who studies at Stony Brook University in New York, was born in Chapel Hill, North Carolina, and is also 37 years old. He made his first original contribution to mathematics: in a deceptively simple problem about the geometry of loops on a plane surface.² – while in high school. He then published several research articles during his undergraduate studies at Princeton, where he also studied Chinese and performed as a cellist in a university orchestra.

During his PhD at Stanford University in California, Pardon partially solved another of Hilbert’s problems.³but mainly he shifted to symplectic and contact geometry, fields that arose from the mathematical description of physical systems, such as the motion of the planets. Symplectic ‘spaces’ always have an even number of dimensions, and contact spaces are their odd-dimensional counterparts that are often found within a symplectic space.

Pardon’s doctoral thesis was a technical feat in which he developed techniques to distinguish two contact spaces. Later, he applied those tools to solve important problems in symplectic and contact geometry, including some that arose from the physics of string theory.⁴ — a speculative framework for interpreting all elementary particles and fundamental forces as vibrations of loops called strings. Mathematicians often model these chains as loops that move from one contact space to another within a symplectic space.

Resonating with equations

Tsimerman’s passion for solving mathematical puzzles began to manifest as early as the age of three, he says. “As long as I can remember, I have been interested in mathematics,” says Tsimerman, 38, a Russian-born Canadian studying at the University of Toronto, Canada.

Its main focus is number theory, particularly whether and how certain equations (known as Diophantine equations) can have integers as solutions. These equations are closely related to algebraic geometry, including the structure of objects with more than three dimensions, called Shimura manifolds. (These also play an essential role in the proof of Fermat’s Last Theorem, one of the most celebrated mathematical advances of the late 20th century.)

One of Tsimerman’s favorite facts is that if Shimura varieties could vibrate like physical objects, each of their resonant frequencies would correspond to a specific Diophantine equation. Tsimerman and his collaborators demonstrated one of the central claims of the theory of Shimura manifolds in 2021⁵called the André-Oort conjecture after the two mathematicians who formulated it, and another important conjecture posed by Phillip Griffiths at the Institute for Advanced Study in Princeton.⁶.