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A Tribute to Boris Weisfeiler

In 1985 the mathematician Boris Weisfeiler disappeared while hiking alone in a remote area of Chile. At the time, he was a professor of mathematics at Pennsylvania State University and was widely recognized for his work in algebraic groups. What happened to him remains a mystery, and to this day it is not known whether he is still alive. Born in the Soviet Union, Weisfeiler received his Ph.D. in 1970 from the Leningrad branch of the Steklov Institute, where his adviser was E. B. Vinberg. Weisfeiler emigrated to the United States in 1975 and worked with Armand Borel at the Institute for Advanced Study. The next year he joined the faculty at Pennsylvania State University. In 1981 he became an American citizen. Weisfeiler’s disappearance has been the subject of several newspaper articles (see, for example, “Chilean Mystery: Clues to Vanished American”, by Larry Rohter, New York Times, May 19, 2002; and “Tracing a Mystery of the Missing in Chile”, by Pascale Bonnefoy, Washington Post, January 18, 2003). Further information about media coverage, as well as the present status of the investigation into his disappearance, may be found at http://weisfeiler. com/boris. On the occasion of the publication in Chile of a book about Weisfeiler’s disappearance, the Notices decided to present a brief tribute to his life and work. What follows is a short summary of his mathematical work and a review of the book. This is not an obituary, as hope remains that Weisfeiler is still alive. Nevertheless, it seems appropriate to commemorate this lost member of the mathematical community, whose absence is keenly felt. —Allyn Jackson