Juergen Moser; Mathematician and Teacher

Juergen Moser, 71, an American mathematician recognized worldwide for proving a theory on the workings of the solar system. Moser’s proof of Russian mathematician Andrei N. Kolmogorov’s theory that the gravitational pull of distant planets may have no apparent effect on elliptical orbits in space was important to the understanding of celestial mechanics and to the development of particle accelerators, which have allowed scientists to test many theories about nature’s tiniest building blocks. Moser was born in Koenigsberg, then an eastern outpost of Germany and now the Russian city of Kaliningrad. He studied at the University of Goettingen in West Germany before going to the United States on a Fulbright fellowship in 1953. Moser went on to become a U.S. citizen and teach at MIT and New York University. He returned to Europe in the 1980s, teaching at the Swiss technology institute. He also served as director of its Research Institute for Mathematics, a post he held until 1995, when we was made professor emeritus. On Friday in Zurich of cancer.