Mark Krein

Mark Grigorievich Krein was a Soviet mathematician who worked in functional analysis, operator theory, classical analysis and representation theory. He was born in Kiev, then in the Russian Empire, on 3 April 1907 and died in Odessa on 17 October 1989. His father was in the wood trade and the family had little money, and because they were Jewish he grew up in an atmosphere of persecution. By fourteen he was already attending research seminars in mathematics in Kiev, and at seventeen he left home and ran away to Odessa without finishing an undergraduate degree. Odessa University accepted him for doctoral studies under Chebotaryov in 1926.