Laurent Siebenmann

Laurent Carl Siebenmann (the first name is sometimes spelled Laurence or Larry) (born in 1939 in Toronto) is a Canadian mathematician based at the Université de Paris-Sud at Orsay, France.

After working for several years as a Professor at Orsay he became a Directeur de Recherches in the French CNRS in 1976. He is a topologist who works on manifolds and who co-discovered the Kirby–Siebenmann class. His undergraduate studies were at the University of Toronto. He received a Ph.D. from Princeton University under the supervision of John Milnor in 1965 with the dissertation The Obstruction to Finding a Boundary for an Open Manifold of Dimension Greater than Five. His doctoral students at Orsay included Albert Fathi.

In 1985 he was awarded the Jeffery–Williams Prize by the Canadian Mathematical Society. In 2012 he became a fellow of the American Mathematical Society.

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