English

Symplectic cohomological rigidity via toric degnerations

Symplectic Geometry 2020-03-02 v1

Abstract

In this paper we study whether symplectic toric manifolds are symplectically cohomologically rigid. Here we say that symplectic cohomological rigidity holds for some family of symplectic manifolds if the members of that family can be distinguished by their integral cohomology rings and the cohomology classes of their symplectic forms. We show how toric degenerations can be used to produce the symplectomorphisms necessary to answer this question. As a consequence we prove that symplectic cohomological rigidity holds for the family of symplectic Bott manifolds with rational symplectic form whose rational cohomology ring is isomorphic to H((CP1)n;Q)\mathrm{H}^*((\mathbb{CP}^1)^n;\mathbb{Q}) for some nn. In particular, we classify such manifolds up to symplectomorphism. Moreover, we prove that any symplectic toric manifold with rational symplectic form whose integral cohomology ring is isomorphic to H((CP1)n;Z)\mathrm{H}^*((\mathbb{CP}^1)^n;\mathbb{Z}) is symplectomorphic to (CP1)n(\mathbb{CP}^1)^n with a product symplectic structure.

Keywords

Cite

@article{arxiv.2002.12434,
  title  = {Symplectic cohomological rigidity via toric degnerations},
  author = {Milena Pabiniak and Susan Tolman},
  journal= {arXiv preprint arXiv:2002.12434},
  year   = {2020}
}

Comments

24 pages

R2 v1 2026-06-23T13:56:55.199Z