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arXiv · 2409.19555

Derived symmetries for crepant contractions to hypersurfaces

W. Donovan
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Abstract

Given a crepant contraction f to a singularity X, we may expect a derived symmetry of the source of f. Under easily-checked geometric assumptions, I construct such a symmetry when X is a hypersurface in a smooth ambient S, using a spherical functor from the derived category of S. I describe this symmetry, relate it to other symmetries, and establish its compatibility with base change.

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W. Donovan. 2024-09-29. Derived symmetries for crepant contractions to hypersurfaces. https://arxiv.org/abs/2409.19555

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