John Stephen Halperin (born 1 February 1942 in Kingston, Ontario)[1] is a Canadian mathematician who deals with differential geometry and algebraic topology.
He received in 1970 his PhD from Cornell University under the supervision of Hsien Chung Wang with thesis Real Cohomology and Smooth Transformation Groups.
His research deals with homotopy theory and homology of loop spaces with applications in geometry.
He wrote a three-volume textbook on differential geometry with Werner H. Greub and Ray Vanstone.
In 1984 Halperin was elected a Fellow of the Royal Society of Canada.