Jean Leray

Jean Leray (1906 to 1998) was a French mathematician who worked on both partial differential equations and algebraic topology. Born in Chantenay-sur-Loire, now part of Nantes, he studied at the Ecole Normale Superieure from 1926 to 1929 and received his doctorate in 1933. In 1934 he published a paper that founded the study of weak solutions of the Navier-Stokes equations, and with Juliusz Schauder he found the topological invariant now called the Leray-Schauder degree. While held as a prisoner of war in a camp in Edelbach, Austria, from 1940 to 1945, he carried out the topological work that proved seminal for spectral sequences and sheaves, tools later developed into central methods of homological algebra. He held chairs at Nancy, Paris and the College de France, where he stayed until 1978, and his honours include the Feltrinelli Prize, the Wolf Prize in Mathematics and the Lomonosov Gold Medal.