Pierre Ossian Bonnet

Pierre Ossian Bonnet (born 22 December 1819 in Montpellier, † June 22, 1892 in Paris) was a French mathematician and professor at the Sorbonne in Paris.

Bonnet studied from 1838 at the École polytechnique and then at the Ecole des Ponts et des Chaussées in Paris. Instead of an engineer, he was then but a mathematician. He taught privately and published mathematical work - one earned him a 1849 price of the Brussels Academy of Sciences. His work on differential geometry, he began 1844. During the same year he received an assistant post at the École polytechnique. In 1862 he was elected to the French Academy of Sciences. In 1868 he became assistant to Michel Chasles at the École polytechnique Directeur d' Études and 1871. In addition, he taught at the École normale supérieure also. Bonnet carried out numerous improvements in teaching mathematics at both an elite high schools. Not least because he was in 1878, as successor of Urbain Le Verrier, professor of astronomy at the Sorbonne. In 1883 he became a member of the Bureau des Longitudes. A short time later, he was fired because of denunciations from all offices.

He provided fundamental contributions to differential geometry. He introduced the Bonnet's plane coordinates, examined minimal surfaces and geodesics on surfaces of positive curvature. Based on these studies, the set of Bonnet was named after him. The Gauss -Bonnet, indicating a formula for the surface curvature, was discovered by Carl Friedrich Gauss and Bonnet. He showed independent of Ferdinand Minding the invariance of geodesic curvature at surface deflections. In addition, Bonnet also dealt with mathematical physics, mechanics and cartography.