Weinstein was born to Judel Lejb Weinstein and Praskovya Levkovich, his family was
Jewish, and his father was a
doctor. His family moved to
Astrakhan, but later decided to emigrate to
Germany, there Weinstein completed his schooling, having studied first in
Würzburg, then at the
University of Göttingen during 1913/14. After his graduation, he left for
Zürich and soon undertook research for
Hermann Weyl and
Rudolf Fueter and was awarded a
doctorate in 1921 for his thesis on the
tensor calculus and linear groups of matrices.
Weyl suggested Weinstein to several prominent mathematicians, including
Paul Sophus Epstein, who was then worked at the
California Institute of Technology. Weinstein was a target of
xenophobia, so he struggled to find a "scientific position adequate to his abilities in Switzerland", as such
Weyl recommended Weinstein for a
Rockfeller Fellowship, with him being awarded it, and spent two years (1926/27) in
Rome, where he worked with
Tulio Levi-Civita. With
Levi-Civita, Weinstein published three more works before he returned to
Zürich as a
privatdocent in
Weyl's chair, then in 1928 he was appointed to the
Hamburg Technical University, he also joined the
German Mathematical Society. He married Marianne Olga Louise Ganz on 13 March 1928 in
Hamburg, they did not have any children. By 1933, he was sought by
Albert Einstein as a collaborator in
Berlin, however after the electoral success of the
Nazi Party, Weinstein, being of
Jewish background, instead went to
Sorbonne and the
Collège de France in
Paris, where he worked with
Jacques Hadamard. He was awarded the degree of Docteur ès Sciences Mathématiques in 1937, and spent a few semesters in
England, at the
University of Cambridge, and the
University of London, before returning to
Paris. In May 1940, after the
Nazi invasion of France, Weinstein and his wife fled to
Portugal with the hope they could seek
refuge to the
United States. They arrived in
New York on 26 October 1940, and lived at 22 West 75th Street, for the next eight years Weinstein taught at a number of different places, and
became a citizen in 1946. Together with Monroe Martin, an expert on
classical analysis and
fluid dynamics, he founded the Institute of Fluid Dynamics and Applied Mathematics (later renamed the
Institute of Physical Science and Technology) at
Maryland in 1949. Weinstein's research covered numerous topics, he is famous for having solved
Helmholtz's problem for jets, giving the first
uniqueness and existence theorem for free jets in his papers from 1923 to 1929, and he examined many
boundary problems, whilst giving hydrodynamic and electromagnetic applications. Weinstein's method was later developed to give accurate bounds of
eigenvalues of plates and membranes, and he introduced a new branch of
potential theory through his examination of singular
partial differential equations. Weinstein retired in 1967, yet continued research at the
American University in
Washington D.C., he worked from 1968 to 1972 at
Georgetown University. In 1972, Weinstein published alongside William Stenger, the book
Methods of Intermediate problems for eigenvalues, and then in 1978, when Weinstein was eighty years old, Joe D Diaz made a collection of Weinstein's writings. He died on 6 November 1979, following a
surgical operation. ==Publications==