Lev Pontryagin

Lev Semyonovich Pontryagin was a Soviet mathematician, born in Moscow on 3 September 1908, who died on 3 May 1988. Completely blind from the age of 14, he made major discoveries in algebraic topology, differential topology and optimal control. He entered Moscow State University in 1925, where Pavel Alexandrov became his doctoral thesis advisor, and in 1934 he joined the Steklov Institute. He laid the foundations of the abstract theory of the Fourier transform, now called Pontryagin duality, with which he solved the case of Hilbert's fifth problem for abelian groups in 1934, and with René Thom he is regarded as a co-founder of cobordism theory, which led to the Pontryagin classes. From 1952 he worked in optimal control theory, where his maximum principle is fundamental to the modern theory of optimization.