Shenzhen-born mathematician wins Fields Medal

Deng Yu, a Shenzhen-born mathematician and professor at the University of Chicago, has won this year's Fields Medal for his contributions to placing the laws of physics on a rigorous mathematical foundation.

Deng Yu. File photos

The Fields Medal, announced July 23 at the International Congress of Mathematicians in Philadelphia, is awarded every four years to up to four mathematicians under the age of 40, recognizing outstanding mathematical achievement and the promise of future contributions. In the absence of a Nobel Prize for mathematics, the Fields Medal is regarded as the highest professional honor a mathematician can attain.

Winning alongside Deng were John Pardon, Jacob Tsimerman, and Wang Hong, who happened to be Deng's classmate in the 2007 cohort at Peking University's School of Mathematical Sciences. The two were also the first Chinese nationals to win the award. Previously, in 1982 and 2006, mathematicians of Chinese descent — Yau Shing-Tung and Terence Tao — stood on that podium. Wang is also only the third woman to win in the award's 90-year history, following the late Maryam Mirzakhani in 2014 and Maryna Viazovska in 2022.

The four Fields Medal recipients are, from left to right, Wang Hong, Jacob Tsimerman, John Pardon and Deng Yu.

This year's four winners represent a range of mathematical subfields, from number theory to mathematical physics.

“This is a great honor for me — an important recognition for my work with collaborators and for the field that I represent," Deng said.

Deng was honored for addressing one of a famous set of problems laid out more than 125 years ago, at the 1900 International Congress of Mathematicians, by German mathematician and philosopher David Hilbert. These problems have since become benchmarks of progress in the field.

Deng Yu gives a presentation during the International Congress of Chinese Mathematicians in Shanghai in January this year.

Specifically, Deng and his collaborators cracked a longstanding problem within the overarching effort to mathematically connect the equations governing the motion of gases from the smallest to the largest scales.

The award also recognizes Deng's research on wave dynamics equations, which laid the foundation for this historic result.

“Deng's beautiful and original work resolves a fundamental problem in mathematical physics that goes back to Hilbert more than a century ago," said Frank Calegari, professor and chair of UChicago's Department of Mathematics. "It also introduces powerful new methods that will shape future research. This is a landmark achievement."

A pattern of problem-solving

Deng's mathematical roots run deep. Born in 1989, the mathematician is an alumnus of Shekou's Yucai Primary School and Shenzhen Senior High School. His father, a computer programmer, would take him hiking and pose little combinatorics problems — the branch of mathematics focused on counting — for him to solve along the way.

In his youth, Deng displayed a gift for problem-solving, excelling in both math competitions and tournaments of Go, an ancient Chinese strategy game played with black and white stones on a grid. Deng said he entertained the idea of becoming a professional Go player before devoting himself to academia.

Deng Yu working on a math problem.

In 2006, at 16 years old, he represented China at the International Mathematical Olympiad and won a gold medal. "At that time, I realized, okay, so maybe I do have some talent in math," said Deng.

The following year, he was admitted to Peking University, later transferring to MIT, where he became a Putnam Fellow in the 2010 William Lowell Putnam Mathematical Competition. Deng earned a bachelor's degree in mathematics in 2011, followed by a Ph.D. from Princeton University in 2015. He joined UChicago in 2024.

Though often labeled a child prodigy with a gift for mathematics, Deng has his own understanding of talent.

He once said, "Talent is somewhat elusive — it's not a fully well-defined concept. Effort is always necessary. If you strive and ultimately succeed, that in itself is proof that you possess some degree of talent. But without effort, talent remains invisible and unmanifested."

Compared with the Nobel Prize, which carries a cash award of about 8 million yuan per individual, the Fields Medal's prize of 15,000 Canadian dollars (US$10,600) plus a 14-karat gold medal per winner is modest. Yet in mathematics, it is globally recognized as the highest honor for young researchers. Over nearly a century, the total number of Fields medalists worldwide stands at only a few dozen — far rarer than Nobel laureates.