On the Voevodsky motive of the moduli space of Higgs bundles on a curve

Abstract

We study the motive of the moduli space of semistable Higgs bundles of coprime rank and degree on a smooth projective curve C over a field k under the assumption that C has a rational point. We show this motive is contained in the thick tensor subcategory of Voevodsky's triangulated category of motives with rational coefficients generated by the motive of C. Moreover, over a field of characteristic zero, we prove a motivic non-abelian Hodge correspondence: the integral motives of the Higgs and de Rham moduli spaces are isomorphic.

26 pages. The material in Appendix A has been moved from a previous paper of ours (arXiv 1711.11072, Section 3 of v1; in v2 this section is removed)