SMS scnews item created by James East at Wed 6 Oct 2010 0950
Type: Seminar
Distribution: World
Expiry: 8 Oct 2010
Calendar1: 8 Oct 2010 1205-1255
CalLoc1: Carslaw 175

Algebra Seminar

Infinite generation of non-cocompact lattices on right-angled buildings

Anne Thomas

Friday October 8, 12:05--12:55pm, Carslaw 175


Let Gamma be a non-cocompact lattice on a locally finite regular right-angled building X. Examples of such X include products of locally finite regular or biregular trees, or Bourdon's building I_{p,q}, which has apartments hyperbolic planes tesselated by right-angled p-gons and all vertex links the complete bipartite graph K_{q,q}. We prove that if Gamma has a strict fundamental domain then Gamma is not finitely generated. The proof uses a topological criterion for finite generation and the separation properties of subcomplexes of X called tree-walls. This is joint work with Kevin Wortman (Utah).


After the seminar we will take the speaker to lunch.

See the Algebra Seminar web page for information about other seminars in the series.

James East