Hans Grauert

Hans Grauert (1930 to 2011) was a German mathematician known for major work on several complex variables, complex manifolds and the use of sheaf theory in that area, which influenced later work in algebraic geometry. Together with Reinhold Remmert he established and developed the theory of complex-analytic spaces. He studied at the University of Munster, where he received his doctorate in 1954, and in 1958 he became professor at the University of Gottingen as successor to Carl Ludwig Siegel, a chair whose line runs back through Weyl, Hilbert and Riemann to Gauss. He remained professor emeritus there until his death. Grauert's approximation theorem, an analogue of Whitney's approximation theorem, states that real-analytic maps between real-analytic manifolds are dense in the smooth maps between them. He wrote Several Complex Variables with Klaus Fritzsche and was honoured with a fellowship of the Leopoldina and the von Staudt Prize.