Jean-Marie Souriau (3 June 1922 – 15 March 2012) was a French mathematician, known for works in symplectic geometry, in which he was one of the pioneers.
He published several works, a treatise on linear algebra [Sou64a], a treatise on relativity [Sou64b] and a treatise on symplectic mechanics [Sou70].
He developed the symplectic aspects of classical and quantum mechanics.
He contributed to the introduction or the development of many important concepts, such as the coadjoint action and the coadjoint orbits of a group on its moment space, which led in particular to the first geometric interpretation of spin at a classical level.
He introduced the moment map, he suggested a program of geometric quantization, he gave a classification of the homogeneous symplectic manifolds, known as the Kirillov-Kostant-Souriau theorem.
Finally, he proposed a new approach to differential geometry by means of diffeologies.
He was educated at the École Normale Supérieure in Paris, and spent most of his career as a Professor of Mathematics at the University of Provence in Marseille.