Bernhard Riemann

It's the birthday of Bernhard Riemann, who was born in 1826 in the German village of Breselenz. At high school and at university, Riemann studied theology, but his interest in and talent for mathematics proved irresistible. On the advice of Carl Gauss, he became a mathematician. To physicists, Riemann is most famous for generalizing and formalizing differential geometry. The mathematical infrastructure that he built was essential to Albert Einstein's theory of general relativity. In his Lecture on Geometry, Riemann sounded like a physicist: "Therefore, either the reality on which our space is based must form a discrete manifold or else the reason for the metric relationships must be sought for, externally, in the binding forces acting on it."