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arXiv · 1011.4689

A Note on Formality and Singularities of Moduli Spaces

Ziyu Zhang
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Abstract

This paper studies formality of the differential graded algebra $RHom(E,E)$, where $E$ is a semistable sheaf on a K3 surface. The main tool is Kaledin's theorem on formality in families. For a large class of sheaves $E$, this DG algebra is formal, therefore we have an explicit description of the singularity type of the moduli space of semistable sheaves at the point represented by $E$. This paper also explains why Kaledin's theorem fails to apply in the remaining case.

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Ziyu Zhang. 2010-11-21. A Note on Formality and Singularities of Moduli Spaces. https://arxiv.org/abs/1011.4689

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