Lev Semenovich Pontryagin (1908-1988) was a Russian mathematician who made important contributions to the theory of topological groups and to algebraic topology.
He is famous for having established the Pontryagin duality? for locally compact abelian groups, thus generalising the Fourier transform to functions defined on general locally compact abelian groups. He also introduced framed cobordism? and its connection with the homotopy groups of spheres. His work was later generalised by René Thom with the Thom-Pontryagin construction? in general cobordism. He introduced the Pontryagin classes for oriented vector bundles.