Sergei Sobolev

Prof Sergei Lvovich Sobolev, FRSE (Серге́й Льво́вич Со́болев; 6 October 1908 – 3 January 1989) was a Soviet mathematician working in mathematical analysis and partial differential equations.

Sobolev introduced notions that are now fundamental for several areas of mathematics. Sobolev spaces can be defined by some growth conditions on the Fourier transform. They and their embedding theorems are an important subject in functional analysis. Generalized functions (later known as distributions) were first introduced by Sobolev in 1935 for weak solutions, and further developed by Laurent Schwartz. Sobolev abstracted the classical notion of differentiation, so expanding the range of application of the technique of Newton and Leibniz. The theory of distributions is considered now as the calculus of the modern epoch.

Life
He was born in St. Petersburg as the son of Lev Alexandrovich Sobolev, a lawyer, and his wife, Natalya Georgievna. His city was renamed Petrograd in his youth and then Leningrad in 1924.

Sobolev studied mathematics at Leningrad University and graduated in 1929, having studied under Professor Nikolai Günther. After graduation, he worked with Vladimir Smirnov, whom he considered as his second teacher. He worked in Leningrad from 1932, and at the Steklov Mathematical Institute in Moscow from 1934. He headed the institute in evacuation to Kazan during World War II. He was a Moscow State University Professor of Mathematics from 1935 to 1957 and also a deputy director of the Institute for Atomic Energy from 1943 to 1957 where he participated in the A-bomb project of the USSR. In 1958, he led with Nikolay Brusentsov the development of the ternary computer Setun.

In 1956, Sobolev joined a number of scientists in proposing a large-scale scientific and educational initiative for the Eastern parts of the Soviet Union, which resulted in the creation of the Siberian Division of the Academy of Sciences. He was the founder and first director of the Institute of Mathematics at Akademgorodok near Novosibirsk, which was later to bear his name, and played an important role in the establishment and development of Novosibirsk State University. In 1962, he called for a reform of the Soviet education system.

He died in Moscow.

Family
In 1930 he married Ariadna Dmitrievna.

Publications
In 1955 he co-wrote The Main Features of Cybernetics with Alexey Lyapunov and Anatoly Kitov which was published in Voprosy filosofii.