The complexity of group presentations, manifolds, and the Andrews-Curtis conjecture

Mon, 25/02
15:45
Martin Bridson (Oxford) Topology Seminar Add to calendar L3
Many natural problems concerning the geometry and topology of manifolds are intimately connected with the nature of presentations for the fundamental groups of the manifolds. I shall illustrate this theme with various specific results, then focus on balanced presentations. I'll explain the (open) Andrews-Curtis conjecture and it's relation to the smooth 4-dimensional Poincare conjecture, and I'll present a construction that gives (huge) lower bounds on how hard it is to distinguish a homology 4-sphere from a genuine sphere.