English

Variations of GIT quotients and dimer combinatorics for toric compound Du Val singularities

Algebraic Geometry 2025-05-02 v2 Combinatorics Representation Theory

Abstract

A dimer model is a bipartite graph described on the real two-torus, and it gives the quiver as the dual graph. It is known that for any three-dimensional Gorenstein toric singularity, there exists a dimer model such that a GIT quotient parametrizing stable representations of the associated quiver is a projective crepant resolution of this singularity for some stability parameter. It is also known that the space of stability parameters has the wall-and-chamber structure, and for any projective crepant resolution of a three-dimensional Gorenstein toric singularity can be realized as the GIT quotient associated to a stability parameter contained in some chamber. In this paper, we consider dimer models giving rise to projective crepant resolutions of a toric compound Du Val singularity. We show that sequences of zigzag paths, which are special paths on a dimer model, determine the wall-and-chamber structure of the space of stability parameters. Moreover, we can track the variations of stable representations under wall-crossing using the sequences of zigzag paths.

Keywords

Cite

@article{arxiv.2309.16112,
  title  = {Variations of GIT quotients and dimer combinatorics for toric compound Du Val singularities},
  author = {Yusuke Nakajima},
  journal= {arXiv preprint arXiv:2309.16112},
  year   = {2025}
}

Comments

39 pages, v2: fixed some proofs

R2 v1 2026-06-28T12:34:28.785Z