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arXiv · 2505.06940

A categorical flop in dimension one

Calum Crossley
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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.

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Calum Crossley. 2025-05-11. A categorical flop in dimension one. https://arxiv.org/abs/2505.06940

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