Jacques Tits

Jacques Tits (born August 12, 1930 in Uccle) is a Belgian mathematician. He has written and cowritten a large number of papers on a number of subjects, principally group theory.

His academic career includes professorships at the Université Libre de Bruxelles (1962-1964), the University of Bonn (1964-1974) and the Collège de France in Paris, until becoming emeritus in 2000. Since 1974 he is member of the French Academy of Sciences.

He introduced the theory of buildings, which are combinatorial structures on which groups act, in many cases of interest in algebraic group theory (including finite groups, and groups defined over the p-adic numbers). The related theory of (B, N) pairs is a basic tool in the theory of groups of Lie type. He also classified all polar spaces of rank at least three and introduced the generalized n-gons. Another of his well known theorems is the "Tits alternative": if G is a finitely generated subgroup of a linear group, then either G has a solvable subgroup of finite index or it has a free subgroup of rank 2.

Tits received the Wolf Prize in Mathematics in 1993, the Cantor Medal from the Deutsche Mathematiker-Vereinigung (German Mathematical Society) in 1996, and the German distinction "Pour le Mérite". He is a member of several Academies of Sciences.

The Tits group is named after him.