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arXiv · 1902.06486

Deformations of polystable sheaves on surfaces: quadraticity implies formality

Ruggero Bandiera·Marco Manetti·Francesco Meazzini
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Abstract

We study relations between the quadraticity of the Kuranishi family of a coherent sheaf on a complex projective scheme and the formality of the DG-Lie algebra of its derived endomorphisms. In particular, we prove that for a polystable coherent sheaf on a smooth complex projective surface the DG-Lie algebra of derived endomorphisms is formal if and only if the Kuranishi family is quadratic.

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Ruggero Bandiera, Marco Manetti, Francesco Meazzini. 2019-02-18. Deformations of polystable sheaves on surfaces: quadraticity implies formality. https://arxiv.org/abs/1902.06486

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