Rudolf Ernest Langer

Rudolf Ernest Langer, also written Rudolph Ernest Langer (1894 to 1968), was an American mathematician and a president of the Mathematical Association of America. He is known for the Langer correction in semiclassical physics. He earned his doctorate at Harvard University in 1922 under G. D. Birkhoff and taught at Dartmouth College from 1922 to 1925. From 1927 to 1964 he was a professor of mathematics at the University of Wisconsin-Madison, and he chaired its mathematics department from 1942 to 1952. From 1956 to 1963 he directed the Army Mathematics Research Center. His doctoral students included Nicholas Kazarinoff, Homer Newell and Henry Scheffé. His published papers treated boundary problems, integral equations and the asymptotic solutions of differential equations, including those of Bessel functions of large order.