English

A categorical flop in dimension one

Algebraic Geometry 2026-03-24 v3

Abstract

In this note we observe that the categorical structure of a flop occurs for some well-known non-commutative resolutions of a nodal curve. We describe the flop-flop spherical twists, and give a geometric interpretation in terms of Landau--Ginzburg models. The resolutions are all weakly crepant but not strongly crepant, and we formulate an intermediate condition that distinguishes the smaller ones.

Keywords

Cite

@article{arxiv.2505.06940,
  title  = {A categorical flop in dimension one},
  author = {Calum Crossley},
  journal= {arXiv preprint arXiv:2505.06940},
  year   = {2026}
}

Comments

v3: final version, incorporating referee suggestions

R2 v1 2026-06-28T23:28:35.785Z