Charles Julien Brianchon

Charles Julien Brianchon ( born December 19, 1783 in Sèvres, † April 29, 1864 in Versailles) was a French mathematician.

Brianchon studied at the École Polytechnique in Paris. In 1808 he was a lieutenant in the artillery. After a period in the army of Napoleon in Italy, Spain and Portugal, he became in 1818 a professor at the School of Artillery of the Royal Guard in Vincennes.

Work

In 1818 he published his book Application de la theory of transverse, in which he deals with the purely linear parts of the plane Euclidean geometry summary (without circuit structures). In 1810 he published a paper in the Journal of the Ecole Polytechnique, be simplified by projecting the spatial configurations on the plane proofs in plane geometry.

Brianchon is known ( = be interchanged dual points and lines ) by the set of Brianchon, a classical theorem of plane geometry, the dual version of the theorem of Pascal.

Brianchon published the sentence in 1806 in the Journal of the Ecole Polytechnique, was about the duality theorem of Pascal but not in the clear. He served as a prime example and motivation for the later developed by Jean -Victor Poncelet and other principle of duality in projective geometry.