1865-1963

French mathematician who made important contributions in prime number theory, integral functions, and singularities of functions. He also made significant contributions in the partial differential equations used extensively in mathematical physics and in boundary value problems. Hadamard was active in politics, especially in the controversial Dreyfus Affair, which involved his relative Alfred Dreyfus. Hadamard's left-leaning politics and campaigns for peace following World War II made him politically unwelcome in the United States, though the support of his colleagues never wavered.