A new approach to the operator formalism for Gromov-Witten invariants of the cap and tube

Abstract

Based on Johnson's operator formula for the equivariant Gromov-Witten theory of ${\mathbb{P}}^1$-orbifolds, we give a new approach to the operator formalism by Okounkov and Pandharipande regarding the ${\mathbb{C}}^{\ast }$-equivariant Gromov-Witten theory of ${\mathbb{P}}^1$ relative to one or two points. We also extend their operator formalism in the non-equivariant specialization to the case where we allow negative contact orders.

42 pages. We add Remark 4.7 on the $r$-degree bound for the Gromov-Witten invariants of ${\mathbb{P}}^1$-orbifolds. Typos corrected. No results affected. Comments are welcome!