On the cohomology of characters stacks for non-orientable surfaces

Abstract

We give a counterexample to a formula suggested by the work of Letellier and Rodriguez-Villegas [28] for the mixed Poincaré series of character stacks for non-orientable surfaces. The counterexample is obtained by an explicit description of these character stacks for (real) elliptic curves. Mathematics subject classification: 14M35,14D23