Alexandre Chorin, a longtime UC Berkeley applied mathematician whose methods made it practical to simulate moving fluids on computers, died Oct. 19 at 88, the university's College of Letters & Science announced.
Chorin's techniques, including the widely taught projection method for solving the equations of incompressible flow, underpin modern computational fluid dynamics. Berkeley says engineers now use them to design cars, aircraft, wind turbines, combustion engines and artificial heart valves, and scientists use them to build climate models. "He left an enduring legacy in mathematics and physics," said Berkeley applied math professor Sunčica Čanić.
From refugee to National Medal of Science
He was born Alexandre Joel Choroszczański in Poland on June 25, 1938. After Germany invaded, his Jewish family escaped through Lithuania and the Soviet Union to British Mandate Palestine, and later moved to Switzerland. He studied mechanical engineering at what is now EPFL in Lausanne, where geometer Georges de Rham encouraged him toward mathematics. During Israeli military service he wrote software for WEIZAC, Israel's first computer, to model ocean tides, which started his interest in computing.
He earned his master's and doctorate at New York University's Courant Institute under Peter Lax, then built his career at Berkeley. President Barack Obama gave him the National Medal of Science in 2014. His other honors include the Norbert Wiener Prize and membership in the National Academy of Sciences and the American Academy of Arts and Sciences.