Ngô Bảo Châu (Vietnamese: [ŋo ɓa᷉ːʊ̯ cəʊ̯], born June 28, 1972) is a Vietnamese-French mathematician at the University of Chicago, best known for proving the fundamental lemma for automorphic forms proposed by Robert Langlands and Diana Shelstad. He is the first Vietnamese national to have received the Fields Medal.
Chau was born in 1972, the only son of an intellectual family in Hanoi, North Vietnam. His father, professor Ngô Huy Cẩn, is full professor of physics at the Vietnam National Institute of Mechanics. His mother, Trần Lưu Vân Hiền, is a physician and associate professor at a herbal medicine hospital in Hanoi.
At age 15, he entered the mathematics specialization class at High School for Gifted Students, Hanoi University of Science (Khối chuyên Tổng Hợp – Đại học Khoa Học Tự Nhiên Hà Nội), formerly known as A0-class. In grades 11 and 12, Chau participated in the 29th and 30th International Mathematical Olympiad (IMO) and became the first Vietnamese student to win two IMO gold medals, of which the first one was won with a perfect score (42/42).
After high school, Chau expected to study in Budapest, but in the aftermath of the fall of Communism in Eastern Europe, the new Hungarian government halted scholarships to students from Vietnam. After visiting Chau's father, Paul Germain, secretary of the French Academy of Sciences, arranged for Chau to study in France. He was offered a scholarship by the French government for undergraduate study at the Paris VI University but he chose the prestigious École Normale Supérieure. He obtained a PhD in 1997 from the Universite Paris-Sud under the supervision of Gérard Laumon. He became a member of CNRS at Paris 13 University from 1998 to 2005, and defended his habilitation degree there in 2003.
He became Professor at Paris-Sud 11 University in 2005. In 2005, at age 33, Chau received the title of professor in Vietnam, becoming the country's youngest-ever professor. Since 2007, Chau has worked at the Institute for Advanced Study, Princeton, New Jersey as well as the Hanoi Institute of Mathematics. He joined the mathematics faculty at the University of Chicago on September 1, 2010. Moreover, since 2011 he is acting as scientific director of the newly founded Vietnam Institute for Advanced Study. He holds both Vietnamese and French citizenship.
Chau first came to prominence by proving, in joint work with Gérard Laumon, the fundamental lemma for unitary groups. Their general strategy was to understand the local orbital integrals appearing in the fundamental lemma in terms of affine Springer fibers arising in the Hitchin fibration. This allowed them to employ the tools of geometric representation theory, namely the theory of perverse sheaves, to study what was initially a combinatorial problem of a number-theoretic nature. Chau eventually succeeded in formulating the proof for the fundamental lemma for Lie algebras in 2008. Together with results from Jean-Loup Waldspurger, who had earlier deduced stronger forms of the fundamental lemma from this result, this completed the proof of the fundamental lemma in all cases. As a result, Chau was awarded a Fields Medal in 2010.
In 2004, Chau and Laumon were awarded the Clay Research Award for their achievement in solving the fundamental lemma proposed by Robert Langlands for the case of unitary groups. Chau's proof of the general case was selected by Time as one of the Top Ten Scientific Discoveries of 2009. In 2010, he received the Fields Medal and in 2011, the Legion of Honour. In 2012 he became a fellow of the American Mathematical Society.