Lipman "Lipa" Bers was an American mathematician born in Riga who created the theory of pseudoanalytic functions and worked on Riemann surfaces and Kleinian groups.
Background
Lipman Bers was born on May 22, 1914 in Riga, Latvia, in the family of Isaac A. and Bertha Weinberg Bers. He spent several years as a child in Saint Petersburg. His family returned to Riga in approximately 1919, by which time it was part of independent Latvia. In Riga, his mother was the principal of a Jewish elementary school, and his father became the principal of a Jewish high school, both of which Bers attended.
Education
Bers attended Jewish elementary school and Jewish high school. After high school, Bers studied at the University of Zurich for a year, but had to return to Riga again because of the difficulty of transferring money from Latvia in the international financial crisis of the time. He continued his studies at the University of Riga, where he became active in socialist politics. Bers received his Doctor of Philosophy in 1938 from the University of Prague.
Career
Bers spent World War II teaching mathematics as a research associate at Brown University, where he was joined by Loewner. After the war, Bers found an assistant professorship at Syracuse University, before moving to New York University and then Columbia University, where he became the Davies Professor of Mathematics, and where he chaired the mathematics department from 1972 to 1975. He was a visiting scholar at the Institute for Advanced Study in 1949–1951.
In 1951 Bers moved to New York University, where he gained a full professorship in 1953. During 1953 he also published the first of a series of important papers on his theory of pseudoanalytic functions and their applications, which he termed quasi-conformal mappings. In the late 1960s, Bers published a textbook, "Calculus", which was a standard for many years.
In 1988, Bers retired from teaching at the City University of New York, where he had been visiting professor since 1984. He continued to give lectures and seminars on various subjects, from Kleinian groups to his experience with the Nazi regime, until his death in 1993. Over the course of his career, Bers advised approximately 50 doctoral students.