Back to Departmental Colloquium: Fall 2004
Departmental Colloquium
Date: Thursday, Nov 11, 2004
Time: 4:15PM
Location: JWB 335
Departmental Colloquium
Weighted L 2 Cohomology of Coxeter Groups
Title |
Weighted L 2 Cohomology of Coxeter Groups |
Abstract |
I will discuss a new type of cohomology, depending on a real parameter q, of a cell complex associated to an infinite Coxeter group W. As q varies these cohomology groups interpolate between ordinary cohomology and cohomology with compact supports. Although these groups are Hilbert spaces (usually infinite dimensional), they can be assigned a “dimension” which is a nonnegative real number. These “dimensions” vary continuously with the parameter q. When q is an integer, they give the L 2 Betti numbers of any regular building of type W and thickness q. |
Algebraic Geometry
Geometric Group Theory