Relative orbifold Gromov-Witten theory and degeneration formula
Bohui Chen, An-Min Li, Shanzhong Sun, Guosong Zhao
TL;DR
This work develops a comprehensive framework for relative Gromov-Witten theory in the orbifold setting by integrating the Li–Ruan degeneration approach with Chen-Ruan orbifold GW theory. It constructs moduli spaces of relative orbifold stable maps, proves their compactness, and equips them with virtual fundamental cycles via a Kuranishi-structure approach, including top and lower strata and gluing analysis. The central result is a degeneration formula that expresses orbifold GW invariants of a degenerated target as sums of relative invariants on the split pieces, incorporating fractional contact data and orbifold monodromies. The methodology advances the understanding of how orbifold structure interacts with degeneration and sets the stage for applications to invariance questions in orbifold quantum cohomology under orbifold flops in dimension three.
Abstract
Relative orbifold Gromov-Witten theory is set-up and the degeneration formula is given.
