Solomon Mikhlin

Solomon Grigoryevich Mikhlin (1908-1990), born Zalman Girshevich Mikhlin in the Belarusian village of Kholmech, was a mathematician who worked in Leningrad, now Saint Petersburg, on linear elasticity, singular integrals and numerical analysis. He studied at Leningrad State University, where Vladimir Smirnov supervised his master thesis and Sergei Sobolev was in his class, received the degree of Doctor of Science in 1935 without first taking the candidate degree, and became a professor in 1937. He is best known for introducing the symbol of a singular integral operator, an idea that led to the theory of pseudodifferential operators, and he wrote monographs and textbooks that became classics. He headed the Laboratory of Numerical Methods at Leningrad State University from 1964 to 1986 and was elected to the Leopoldina in 1970 and the Accademia Nazionale dei Lincei in 1981.