Elwin Bruno Christoffel

Elwin Bruno Christoffel was a German mathematician, born on 10 November 1829 in Montjoie, now Monschau near Aachen, who died in Strasbourg on 15 March 1900. He studied in Berlin, where Dirichlet had the greatest influence on him, and took his doctorate in 1856 with a dissertation on the motion of electricity in homogeneous bodies. He later held chairs at the Polytechnic in Zurich, the Gewerbsakademie in Berlin and the University of Strasbourg, where he built up a new institute for mathematics and supervised six doctoral students. He published on conformal mappings, including the Christoffel-Schwarz formula, on potential theory, tensor analysis, the theory of invariants, orthogonal polynomials and continued fractions, and on the propagation of plane waves, an early contribution to the theory of shock waves. His 1858 generalisation of Gauss's method of quadrature is now called Christoffel's theorem.