Introduction

Abstract

The technique of virtual fundamental cycles (and chains) was introduced in the year 1996 by several groups of mathematicians [FOn2, LiTi2, LiuTi, Ru2, Sie] to provide a differential geometric foundation on the study of moduli spaces of pseudo-holomorphic curves entering on the one hand in the Gromov–Witten theory and on the other in the study of the Arnold conjecture in symplectic geometry without the assumption of any kind of positivity on general compact symplectic manifolds. © Springer Nature Singapore Pte Ltd 2020.