Grigory Margulis

Grigory Aleksandrovich Margulis is a Russian American mathematician, born in Moscow on 24 February 1946, who is known for his work on lattices in Lie groups and for the introduction of methods from ergodic theory into diophantine approximation. At the age of 16 he won the silver medal at the International Mathematical Olympiad, and he received his PhD in 1970 from Moscow State University under the supervision of Yakov Sinai. His superrigidity theorem of 1975 clarified classical conjectures about the characterisation of arithmetic groups among lattices in Lie groups, and his early work with David Kazhdan produced the Kazhdan-Margulis theorem. He was awarded the Fields Medal in 1978 but was not permitted to travel to Helsinki to accept it, and he later received the Wolf Prize in 2005 and the Abel Prize in 2020. In 1991 he joined the faculty of Yale University.