James G. Arthur, Member in the School of Mathematics (1976–77, Spring 1984, 1994–95, 2000–2002) and Institute Trustee (1997–2007), will receive the 2017 AMS Leroy P. Steele Prize for Lifetime Achievement "for his fundamental contributions to number theory and harmonic analysis, and in particular for his proof of the Arthur-Selberg trace formula." Arthur is a University Professor and holds the Ted Mossman Chair in Mathematics at the University of Toronto.

James G. Arthur has made deep and lasting contributions to mathematics. The pinnacle of his work is the Arthur-Selberg trace formula, which elucidates profound connections between properties of numbers on the one hand, and geometric shapes on the other. Building on the pioneering work of Atle Selberg, Professor Emeritus School of Mathematics (1987–2007), Professor (1951–1987), and Member in the School (1947–48, 1949–51), Arthur created a whole mathematical framework and introduced many major tools. The Arthur-Selberg trace formula is developed in 16 long and difficult research papers that Arthur published between 1974 and 1988. His work on the trace formula, which continues to this day, stands at the center of a highly active research area to which many mathematicians the world over are contributing.

Read more at American Mathematical Society.