Mathematics Colloquium
3:00 p.m.
Math Annex 1100
Ian Hambleton
Department of Mathematics and Statistics
McMaster University
Symmetries of 4manifolds
The striking differences between smooth and topological
4manifolds are also reflected in their symmetries. It seems
that smooth 4manifolds tend to be much more "rigid" than
their topology predicts, particularly from the viewpoint
of the finite groups of symmetry. One explanation may be
that smooth 4manifolds have extra "hidden" constraints
on their symmetry arising from gauge theory, i.e. the moduli
spaces of solutions for certain PDEs on the manifold. In this
talk we will describe some examples of this principle in
operation, and mention some open problems.
Refreshments will be served at 2:45 p.m. in the Faculty Lounge,
Math Annex (Room 1115).
