Karl Stein (mathematician)
Karl Stein (1 January 1913, Hamm, Westphalia – 19 October 2000) was a German mathematician. He is well known for complex analysis and cryptography. Stein manifolds and Stein factorization are named after him.
Karl Stein received his doctorate with his dissertation on the topic Zur Theorie der Funktionen mehrerer komplexer Veränderlichen; Die Regularitätshüllen niederdimensionaler Mannigfaltigkeiten at the University of Münster unter the supervision of Heinrich Behnke in 1937. In 1955 he became professor at the Ludwig Maximilians University of Munich and emeritated in 1981. In 1990 he received the first Cantor medal.