English

Splitting the diagonal for broken maps

Symplectic Geometry 2025-04-23 v1

Abstract

In previous work, we introduced a version of the Fukaya algebra associated to a degeneration of a symplectic manifold, whose structure maps count collections of maps in the components of the degeneration satisfying matching conditions. In this paper, we introduce a further degeneration of the matching conditions (similar in spirit to Bourgeois' version of symplectic field theory) which results in a "split Fukaya algebra" whose structure maps are, in good cases, sums of products over vertices of tropical graphs. In the case of toric Lagrangians contained in a toric component of the degeneration, an invariance argument implies the existence of projective Maurer-Cartan solutions, which gives an alternate proof of the unobstructedness result of Fukaya-Oh-Ohta-Ono for toric manifolds. Our result also proves unobstructedness in more general cases, such as for toric Lagrangians in almost toric four-manifolds.

Keywords

Cite

@article{arxiv.2504.15583,
  title  = {Splitting the diagonal for broken maps},
  author = {Sushmita Venugopalan and Chris Woodward},
  journal= {arXiv preprint arXiv:2504.15583},
  year   = {2025}
}

Comments

53 pages, 13 figures. This paper has been split off from arXiv:2004.14314

R2 v1 2026-06-28T23:06:42.069Z