# Ian Hambleton: Finite Group Actions and Chain Complexes over the Orbit Category

**Time: **
Thu 2019-09-19 10.15 - 12.00

**Location: **
Room 33, Building 5, Kräftriket, SU

**Participating: **
Ian Hambleton, McMaster University

### Abstract

We consider the existence of finite G-CW complexes X homotopy equivalent to spheres, for which the G-action on X has rank one isotropy. A variety of techniques are involved, including homological algebra over the orbit category. New infinite families of non-linear actions are constructed. This is joint work with Semra Pamuk and Ergun Yalcin.