Mark Krein

Mark Grigorievich Krein was a Soviet mathematician, born in Kiev on 3 April 1907 and one of the major figures of the Soviet school of functional analysis. He left home at seventeen for Odessa and had a difficult academic career, never completing his first degree and repeatedly facing antisemitic discrimination, with Nikolai Chebotaryov as his supervisor. He is known for work in operator theory, closely tied to concrete problems from mathematical physics, as well as the problem of moments, classical analysis and representation theory. Several results carry his name, including the Krein-Milman theorem, the Krein-Rutman theorem, Krein spaces and the Tannaka-Krein duality. His students included David Milman, Mark Naimark, Israel Gohberg, Vadym Adamyan and Mikhail Livsic. He was awarded the Wolf Prize in Mathematics in 1982, jointly with Hassler Whitney, but was not allowed to attend the ceremony. He died in Odessa on 17 October 1989, and a memorial plaque was unveiled on the main administration building of Odesa University in 2008.