1897-1958

English physicist who developed new methods of numerical analysis. Douglas Rayner Hartree was born in Cambridge, England. He entered St. John's College, Cambridge in 1915, but was called away from his studies to join a team studying anti-aircraft gunnery during World War I. After the war, he completed his studies at Cambridge and went on to earn his doctorate in 1926. From 1929-37 he served as chair of theoretical physics at Manchester, Cambridge. As a physicist, Rayner developed both new methods of numerical analysis, as well as ways of using differential equations to calculate atomic wave functions. Before computers had been invented, he developed a differential analyzer which calculated sophisticated equations. When J. Presper Eckert, Jr. (1913-1995) developed his ENIAC computer, Hartree traveled to the United States to assist the machine with its earliest calculations.