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arXiv · 2403.04339

On a conjecture on aCM and Ulrich sheaves on degeneracy loci

Vladimiro Benedetti·Fabio Tanturri
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Abstract

In this paper we address a conjecture by Kleppe and Mir\'o-Roig stating that suitable twists by line bundles (on the smooth locus) of the exterior powers of the normal sheaf of a standard determinantal locus are arithmetically Cohen--Macaulay, and even Ulrich when the locus is linear determinantal. We do so by providing a very simple locally free resolution of such sheaves obtained through the so-called Weyman's Geometric Method.

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Vladimiro Benedetti, Fabio Tanturri. 2024-03-07. On a conjecture on aCM and Ulrich sheaves on degeneracy loci. https://arxiv.org/abs/2403.04339

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