Pisier (born 18 November 1950) is a professor of mathematics at the Pierre and Marie Curie University and a distinguished professor and A.G.
and M.E.
Owen Chair of Mathematics at the Texas A&M University.
He is known for his contributions to several fields of mathematics, including functional analysis, probability theory, harmonic analysis, and operator theory.
He has also made fundamental contributions to the theory of C*-algebras.
Gilles is the younger brother of French actress Marie-France Pisier.