---
abstract: 'We exploit the geometric approach to the virtual fundamental class, due to Fukaya-Ono and Li-Tian, to compare Gromov-Witten invariants of a symplectic manifold and a symplectic submanifold whenever all constrained stable maps to the former are contained in the latter to first order. Various special cases of the comparison theorem in this paper have long been used in the algebraic category; some of them have also appeared in the symplectic setting. Combined with the inherent flexibility of the symplectic category, the main theorem leads to a confirmation of Pandharipande’s Gopakumar-Vafa prediction for GW-invariants of Fano classes in 6-dimensional symplectic manifolds. The proof of the main theorem uses deformations of the Cauchy-Riemann equation that respect the submanifold and Carleman Similarity Principle for solutions of perturbed Cauchy-Riemann equations. In a forthcoming paper, we apply a similar approach to relative Gromov-Witten invariants and the absolute/relative correspondence in genus $0$.'
author:
- 'Aleksey Zinger[^1]'
title: |
    A Comparison Theorem for Gromov-Witten Invariants\
    in the Symplectic Category
---

Introduction {#intro_sec}
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Gromov-Witten invariants are certain counts of pseudo-holomorphic curves in symplectic manifolds that play prominent roles in symplectic topology, algebraic geometry, and string theory. These are usually rational numbers, and their precise relations 