Tom Hutchcroft, the Gordon and Betty Moore Professor of Mathematics at Caltech, has received the 2025 Whitehead Prize from the London Mathematical Society. The prize is awarded yearly to mathematicians working in the United Kingdom, or educated there, who are at an early stage of their career. Hutchcroft earned his bachelor's degree in mathematics from Cambridge University in 2013.
Hutchcroft's award citation states that he is being honored for "for solving numerous fundamental problems in several areas of probability theory. He has exhibited deep creativity and ingenuity, primarily in the interplay between the geometry of graphs (especially Cayley graphs of groups) and the behavior of probabilistic processes on them."
Hutchcroft is an expert in probability theory—more specifically Bernoulli percolation theory, named after the 17th-century mathematician Jacob Bernoulli, who made significant early contributions to probability theory. Bernoulli percolation theory is the study of the complex math that occurs when percolating systems, such as water traveling through ground espresso beans or diseases spreading through populations, exhibit phase transitions. During these critical phases, fractal-like mathematical objects emerge.
Hutchcroft has solved several key problems within this theory, some of which involve mathematical objects called Cayley graphs—visual ways to study geometry in settings that are highly symmetric but could be very different from the familiar "flat" Euclidean geometry of everyday life. "Hutchcroft is unquestionably the leader in understanding percolation on Cayley graphs in general," according to the London Mathematical Society's long citation.
Also mentioned in the award citation are Hutchcroft's "beautiful papers on random walks," which are mathematical paths in which one random step occurs after another in succession. "Among Hutchcroft's impressive contributions in this area, he established several fundamental conjectures in the field that had been open since the late 1990s."
After graduating from Cambridge, Hutchcroft earned his PhD in mathematics from Canada's University of British Columbia in 2017. He held internships at Microsoft Research during his graduate studies and later completed postdoctoral fellowships at the University of Cambridge from 2017 to 2021. He joined the Caltech faculty in 2021.
In 2024, he received the Packard Fellowship for Science and Engineering, an honor that comes with a grant of $875,000 over five years to pursue research.