The creater of von Neumann's inequality, was what nationality?
Von Neumann's inequality In operator theory, von Neumann's inequality, due to John von Neumann, states that, for a fixed contraction "T", the polynomial functional calculus map is itself a contraction.
Nikolai Günther Nikolai Maximovich Günther (Russian: Николай Максимович Гюнтер , also transliterated as Nicholas M. Gunther or N. M. Gjunter) (December 17 [O.S. December 5] 1871 – May 4, 1941) was a Russian mathematician known for his work in potential theory and in integral and partial differential equations: later studies have uncovered his contributions to the theory of Gröbner bases.