Fritz John

Fritz John (1910–1994) was a German born mathematician specialising in partial differential equations and ill-posed problems. His early work was on the Radon transform and he is remembered for John's equation.

He studied mathematics from 1929 to 1933 in Göttingen where he was influenced by Richard Courant among others. With Hitler's rise to power in 1933"non-aryans" were being expelled from teaching posts and John decided to go to England.

John published his first paper in 1934 on Morse theory. He was awarded his doctorate in 1934 from Göttingen and with Richard Courant's assistance spent a year at St John's College, Cambridge. During this time he published papers on the Radon transform, a theme to which he would return.

John was appointed an assistant professor at the University of Kentucky in 1935 and he emigrated to the United States becoming naturalised in 1941. He stayed at Kentucky until 1946 apart from 1943 to 1945 during which he did war service for the Ballistic Research Laboratory at the Aberdeen Proving Ground, Maryland. In 1946 he moved to New York University where he remained.

Throughout the 1940s and 1950s he continued to work on the Radon transformin particular its application to linear partial differential equations, convex geometry, and the mathematical theory of water waves. He also wrote on numerical analysis and ill-posed problems.

From the mid 1950s he started working on the theory of equilibrium nonlinear elasticity. He retired in 1981 but continued to work on nonlinear waves.

He was awarded many awards during his career including the Birkhoff Prize in Applied Mathematics in 1973 and the Steele Prize in 1982.

ee also

* John ellipsoid
* John's equation

References

*MacTutor Biography|id=John|title=Fritz John
*S.Klainerman, S On the work and legacy of Fritz John, 1934-1991. Dedicated to the memory of Fritz John. Comm. Pure Appl. Math. 51 (1998), no. 9-10, 991--1017.
*
* Fritz John, Obituary by Jurgen Moser, Notices of the AMS, vol 42, No2, 1995 [http://www.ams.org/notices/199502/people.pdf]

External links

*MathGenealogy |id=33909