Stefan Banach (March 30, 1892 in Kraków, Austria-Hungary now Poland– August 31, 1945 in Lwów, Soviet Union - occupied Poland), was an eminent Polish mathematician, one of the moving spirits of the Lwów School of Mathematics in pre-war Poland. He was largely self-taught in mathematics; his genius was accidentally discovered by Juliusz Mien and later Hugo Steinhaus.

When World War II began, Banach was President of the Polish Mathematical Society and a full professor of University of Lwów. Being a corresponding member of Academy of Sciences of the Ukrainian SSR, and otherwise on good terms with Soviet mathematicians, he was allowed to keep his chair despite the Soviet occupation, from 1939, of the city. Banach survived the subsequent brutal German occupation from July 1941 up to February 1944, earning a living by feeding lice with his blood in the Typhus Research Institute of Prof. Rudolf Weigl. His health declined during the occupation, and he developed lung cancer. After the war Lwów was incorporated into the Soviet Union, and Banach died there before he could be repatriated to Kraków, Poland. He is buried at the Lyczakowski Cemetery.

Work

Théorie des opérations linéaires (Teoria operacji liniowych, 1932) is regarded as Banach's most influential work. In it he formulated the concept now known as Banach space, and proved many fundamental theorems of functional analysis. He also initiated and edited the journal Studia Mathematica.

Besides being one of the founders of functional analysis, Banach also made important contributions to measure theory, set theory, and other branches of mathematics.

Quotes

Stanisław Marcin Ulam, another mathematician of the Lwów School of Mathematics, in his autobiography, attributes this to Banach:

"Good mathematicians see analogies. Great mathematicians see analogies between analogies."

Hugo Steinhaus said of Banach:

"An exceptional intellect, exceptional discoveries...he gave Polish science...more than anybody else."

Hugo Steinhaus:

"Banach was my greatest scientific discovery."

See also

• Banach space
• Banach algebra
• Banach-Steinhaus theorem
• Banach–Tarski paradox
• Hahn-Banach theorem
• Banach fixed point theorem
• Banach-Schauder theorem
• Banach-Alaoglu theorem

External links

• Théorie des opérations linéaires French translation from 1932
• The MacTutor History of Mathematics archive Article on Stefan Banach

1892 births | 1945 deaths | People from Kraków | Polish mathematicians | 20th century mathematicians

ستيفن باناخ | Stefan Banach | Stefan Banach | Stefan Banach | Stefan Banach | 스테판 바나흐 | Stefan Banach | Stefan Banach | סטפן בנך | Stefans Banahs | Stefan Banach | Stefan Banach | ステファン・バナフ | Stefan Banach | Банах, Стефан | Stefan Banach | Stefan Banach | Банах Стефан | 斯特凡·巴拿赫