Topology Seminar: Dale Rolfsen

  • Date: 10/09/2013
  • Time: 15:15
Dale Rolfsen (UBC)

University of British Columbia


Groups of PL homeomorphisms


Let M be a connected, orientable, piecewise linear manifold of dimension n and let B be a closed submanifold of M. Let PL(M, B) be the group of orientation preserving PL homeomorphisms of M which are pointwise fixed on B. The group operation is composition of functions.


In joint work with Danny Calegari we show that if B has codimension zero or one, the group PL(M,B) is locally indicable. This means that every finitely-generated subgroup has the integers as a quotient. It follows that PL(M,B) is left-orderable and therefore has no elements of finite order.

Other Information: 

Location: ESB 4133