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arXiv · 2502.20094

Higher-dimensional O'Grady's resolutions and their exceptional locus

Luigi Martinelli
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Abstract

For any $n \ge 3$, we consider the moduli space $M_n$ of semistable sheaves with Mukai vector $2(1,0,1-n)$ on a K3 surface. The moduli space $M_n$ is singular and lacks a crepant resolution, but might still admit a categorical crepant one. As a preliminary to exploring this possibility, we study the explicit resolution of singularities of $M_n$ constructed by O'Grady, and provide a global description of its exceptional locus.

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Luigi Martinelli. 2025-02-27. Higher-dimensional O'Grady's resolutions and their exceptional locus. https://arxiv.org/abs/2502.20094

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