A Residue Formula for $\SU(2)$-Valued Moment Maps

http://dx.doi.org/10.4153/CMB-2004-058-1
Canad. Math. Bull. 47(2004), 607-614

  Published:2004-12-01
 Printed: Dec 2004

Jeffrey and Kirwan gave expressions for intersection pairings on the reduced space $M_0=\mu^{-1}(0)/G$ of a Hamiltonian $G$-space $M$ in terms of multiple residues. In this paper we prove a residue formula for symplectic volumes of reduced spaces of a quasi-Hamiltonian $\SU(2)$-space. The definition of quasi-Hamiltonian $G$-spaces was recently introduced in .