Gromov--Witten invariants of root stacks with mid-ages and the loop axiom
arXiv:2003.09838
Abstract
We study orbifold Gromov--Witten invariants of the -th root stack with a pair of mid-ages when is sufficiently large. We prove that genus invariants with a pair of mid-ages and are polynomials in and the -coefficients are polynomials in with degree bounded by . Moreover, genus zero invariants with a pair of mid-ages are independent of the choice of mid-ages. As an application, we obtain an identity for relative Gromov--Witten theory which can be viewed as a modified version of the usual loop axiom.
24 pages. Revised according to referees' comments. To appear in Advances in Mathematics