Rational singularities, quiver moment maps, and representations of surface groups

Abstract

We prove using jet schemes that the zero loci of the moment maps for the quivers with one vertex and at least two loops have rational singularities. This implies that the spaces of representations of the fundamental group of a compact Riemann surface of genus at least two have rational singularities. This has consequences for the representation zeta function of the special linear group over the integers and over the p-adic integers.