Jean-Loup Waldspurger (born 2 July 1953) is a French mathematician working on the Langlands program and related areas.
He played a role in the proof of the fundamental lemma, reducing the conjecture to a version for Lie algebras.
Waldspurger attained his doctorate at École normale supérieure in 1980, under supervision of Marie-France Vignéras.
With C. Moeglin, he demonstrated Jacquet's conjecture describing the discrete spectrum of the GL(n) groups.
With C. Moeglin, he wrote two large volumes establishing the stable trace formula for twisted spaces.