tt*-geometry in quantum cohomology

Abstract

We study possible real structures in the space of solutions to the quantum differential equation. We show that, under mild conditions, a real structure in orbifold quantum cohomology yields a pure and polarized tt^*-geometry near the large radius limit. We compute an example of P^1 which is pure and polarized over the whole Kaehler moduli space H^2(P^1,C^*).

34 pages. This paper is a revision of the real structure part of the preprint arXiv:0712.2204