DOUGLAS, JESSE

born July 3, 1897, New York City, N.Y., U.S. died Oct. 7, 1965, New York American mathematician who was awarded one of the first two Fields Medals in 1936 for solving the Plateau problem. Douglas attended City College of New York and Columbia University (Ph.D., 1920). He remained at Columbia until 1926, when he was awarded a National Research Fellowship. He subsequently held appointments at the Massachusetts Institute of Technology (193036) and the Institute for Advanced Study, Princeton, N.J. In 1942 he returned to New York, where he taught at Columbia (194254) and City College of New York (195565). Douglas was awarded the Fields Medal at the International Congress of Mathematicians in Oslo, Nor., in 1936 for work on the celebrated Plateau problem, which had first been posed by the Italian-French mathematician Joseph-Louis Lagrange in 1760. The Plateau problem is one of finding the surface with minimal area determined by a fixed boundary. Experiments (1849) by the Belgian physicist Joseph Plateau demonstrated that the minimal surface can be obtained by immersing a wire frame, representing the boundaries, into soapy water. Douglas developed what is now called the Douglas functional, so that by minimizing this functional he could prove the existence of the solution to the Plateau problem. Early specific cases studied included the classical isoperimetric problem and the problem of determining the minimal surface connecting two parallel circles perpendicular to a line connecting their centres. The answer to the first problem is the circle and to the second a rotated catenary. The general problem of finding the surfaces, where solutions are known to exist, was solved by the classical calculus of variations, an application of the Euler-Lagrange equations. Douglas later developed an interest in group theory, where he made important contributions in 1951 to the problem of determining finite groups on two generators, a and b, with the property that every group element can be expressed in the form akbl, where k and l are integers. Douglas' publications include, with Philip Franklin, Cassius Jackson Keyser, and Leopold Infeld, Galois Lectures (1941).