GoKawiilThe four Fields Medal recipients are, from left to right, Hong Wang, Jacob Tsimerman, John Pardon and Yu Deng.Credit: Simons Foundation
Mathematicians Yu Deng, John Pardon, Jacob Tsimerman and Hong Wang have won the 2026 Fields Medal — one of the most coveted awards in their discipline. Their names were revealed at the International Congress of Mathematicians (ICM) today in Philadelphia, Pennsylvania.
The four winners represent a range of subfields of maths, from number theory to mathematical physics. They had all been rumoured as favourites to win the medal, which is awarded every four years to up to four mathematicians under the age of 40.
The winners all work in North America, but two — Deng and Wang — were born and raised in China. They are only the second and third Chinese nationals to have earned a Fields Medal: Shing-Tung Yau, who is now at Tsinghua University in Beijing, won his in 1982, before either Deng or Wang were born. Wang is also only the third woman to win in the award’s 90-year history, after the late Maryam Mirzakhani in 2014 and Maryna Viazovska in 2022.
Irreversible fluids
Deng, who is 37 and grew up in Shenzhen, did his PhD 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 he had won the medal made him “really happy, not just for myself, but for the field I’m representing”.
Deng’s most celebrated achievement was a breakthrough on one of the problems posed by German mathematician David Hilbert in a historic talk at the ICM in 1900: he challenged mathematicians to reconcile the behaviour and smooth appearance of fluids with the idea (still not broadly accepted at that time) that they were made of multitudes of atoms or molecules.
Together with two collaborators1, Deng found a rigorous proof that the microscopic jostling of many constituent particles — acting like tiny billiard balls continuously bouncing off one another — produces as a necessary consequence a differential equation formulated in the late 1800s to describe fluids.
‘Mathematics is an unknown land’: meet Fields Medal winner Maryna Viazovska
This helped to reconcile an apparent conundrum. Microscopic physics works just as well when time is reversed — meaning that it might be impossible to tell if a movie of two molecules bouncing off each other is being played forwards or backwards. But when many molecules form a fluid, they have an unavoidably irreversible behaviour: if you mix a cold gas with a hot one, say, the mixture will never spontaneously separate back into hot and cold.
... continue reading