The Quarterly Journal of Mathematics Advance Access published online on January 21, 2009
The Quarterly Journal of Mathematics, doi:10.1093/qmath/han040
MODULI SPACES OF FLAT SU(2)-BUNDLES OVER NON-ORIENTABLE SURFACES

Department of Mathematics, University of Toronto, Toronto, Ont., Canada M5S 2E4
Presently at Mathematical Institute, University of Oxford, 24–29 St. Giles, Oxford OX1 3LB, UK. E-mail: baird{at}maths.ox.ac.uk
Received 1 December 2008;
| Abstract |
|---|
We study the topology of the moduli space of flat SU (2)-bundles over a non-orientable surface
. This moduli space may be identified with the space of homomorphisms Hom (
1(
), SU (2)) modulo conjugation by SU (2). In particular, we compute the (rational) equivariant cohomology ring of Hom (
1(
), SU (2)) and use this to compute the ordinary cohomology groups of the quotient Hom (
1(
), SU (2))/SU (2). A key property is that the conjugation action is equivariantly formal.