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arXiv · 2104.13331

A note on semiorthogonal indecomposability for some Cohen-Macaulay varieties

Dylan Spence
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Abstract

In this short note, we observe that Theorem 3.1 in arXiv:1508.00682 for semiorthogonal indecomposability of the derived category of smooth DM stacks based on the canonical bundle can be extended to the case of projective varieties with Cohen-Macaulay singularities. As a consequence, all projective curves of positive arithmetic genus have weakly indecomposable bounded derived categories and indecomposable categories of perfect complexes. Here weak indecomposablility refers to the admissibility of components.

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Dylan Spence. 2021-04-27. A note on semiorthogonal indecomposability for some Cohen-Macaulay varieties. https://arxiv.org/abs/2104.13331

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