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arXiv · 2107.07490

Deformations of categories of coherent sheaves via quivers with relations

Severin Barmeier·Zhengfang Wang
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Abstract

We give an explicit combinatorial description of the deformation theory of the Abelian category of (quasi)coherent sheaves on any separated Noetherian scheme $X$ via the deformation theory of path algebras of quivers with relations, by using any affine open cover of $X$, or any tilting bundle on $X$, if available. We also give sufficient criteria for obtaining algebraizations of formal deformations, in which case the deformation parameters can be evaluated to a constant and the deformations can be compared to the original Abelian category on equal terms. We give concrete examples as well as applications to the study of noncommutative deformations of singularities.

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Severin Barmeier, Zhengfang Wang. 2021-07-15. Deformations of categories of coherent sheaves via quivers with relations. https://doi.org/10.14231/ag-2024-001

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