Olinde Rodrigues

Benjamin Olinde Rodrigues ( born October 6, 1795 in Bordeaux, † December 17, 1851 in Paris) was a French mathematician, banker and social reformer.

Rodrigues was the eldest of eight children of a Jewish (originally the family came probably from Portugal) accountant, banker and stockbroker born in Bordeaux, but soon moved with his family to Paris. There he attended the Lycée Louis -le- Grand and then studied after it first ( before his old classmates Michel Chasles ) polytechnique in the entrance examinations for the elite École Normale Supérieure and École schools was, at the newly founded University of Paris. Perhaps at that time the Jews were no longer allowed at the two elite French schools. In 1816 he was awarded a doctorate in mathematics. In his dissertation he gave the Rodrigues formula for Legendre polynomials on (published in Mémoire sur l' attraction of spheroides. ) 1835 by James Ivory and Carl Gustav Jacobi independently rediscovered (Charles Hermite and Heinrich Eduard Heine wrote it again Rodrigues ). After that, he was a banker, and brought it to wealth among other financings for French railway system. In part, this was due to the fact that he had no chance of Mathematics Chair with the onset of the reaction as a Jew. Rodrigues was active in the socialist movement and supported, for example, Henri de Saint -Simon, to whom he after a suicide attempt again helped 1823 on the legs and financially supported, and, after his death, one of the leaders of the Saint -Simonians, but broke up in 1832 by them than him some ideas were too radical.

He is best known today were rediscovered especially for a paper from the year 1840 ( Annales de Gergonne ), in which he detailed rotations in three-dimensional space using quaternions, the later ( 1843) by William Rowan Hamilton. Rodrigues also associated correctly half the angle with quaternion rotations (unlike Hamilton), according to the representation of a two-fold superposition of the rotation group. He also examined infinitesimal rotations and took it results from the theory of Lie groups anticipated. The Rodrigues formula of this theme is linked with his name.

Sometimes his name is misquoted in the literature. Elie Cartan example quoted him as the authors Olinde Rodrigues and. Olinde is, moreover, a first name, which he accepted as a child in the naturalization of Jews in France as " French name".

Another result of Rodrigues to Combinatorics ( a generating function for the number of incorrect items on permutations of objects, Liouville's Journal 1839) was re-discovered by Leonard Carlitz 1970. A recursion formula of Rodrigues for partitioning a polygon into triangles was taken by Eugen Netto in his textbook on combinatorics.