Karl Schwarzschild

Karl Schwarzschild (1873-1916), German astronomer, mathematician, and physicist, born in Frankfurt, who predicted the existence of black holes. His first two papers on astronomy were published while still a schoolboy. After studying at the universities of Strasbourg and Munich, he was appointed Director of the Göttingen Observatory in 1901, and of the Astrophysical Observatory in Potsdam in 1909. He volunteered for military service at the start of World War I, but was invalided home in 1916 after contracting a rare skin disease, from which he died. His contributions were in the main theoretical, and related to solar physics, relativity, stellar kinematics, photographic magnitudes, the study of rotating fluid masses, and geometrical optics. In 1916 he postulated the Schwarzschild radius, on the basis of the general theory of relativity newly propounded by Albert Einstein. When a massive star explodes as a supernova, it may leave a remnant so compact that it lies wholly within this radius. Nothing, not even light, can escape from its intense gravitational field. Such objects are now known as black holes.