Stefan Witzel
Stefan Witzel

I'm a postdoc at the Faculty of Mathematics of Bielefeld University where I obtained my habilitation in 2017. Before I was a postdoc in Münster. I did my PhD in Darmstadt.

My research interests fall into the area of geometric group theory, that is, I study groups using geometric and topological tools. Many of the groups I am interested in act on Bruhat-Tits buildings; this is the case for example for S-arithmetic groups. Another class of groups I have become interested in are relatives of Thompson's groups F, T and V. A common feature is that these groups act on CAT(0) spaces, although not cocompactly. I am particularly interested in finiteness properties of groups, which means that I try to find highly connected, cocompact spaces for the groups to act on.

My student Eduard Schesler works on Sigma-invariants of S-arithmetic subgroups of Borel groups.


Faculty of Mathematics
Bielefeld University
Universitätsstraße 25
D-33615 Bielefeld

Mail Address

Faculty of Mathematics
Bielefeld University
Postfach 100131
D-33501 Bielefeld

Office: V4-204
Phone: +49 (521) 106 4986
Fax: +49 (521) 106 6480
Email: switzel [at]

Last modified: Tue 12 Sep 2017, 13:09