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arXiv · 2405.00580

Semiorthogonal decompositions for generalized Severi-Brauer schemes

Ajneet Dhillon·Sayantan Roy Chowdhury
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Abstract

The purpose of this paper is to use conservative descent to study semi-orthogonal decompositions for some homogeneous varieties over general bases. We produce a semi-orthogonal decomposition for the bounded derived category of coherent sheaves on a generalized Severi-Brauer scheme. This extends known results for Sever-Brauer varieties and Grassmanianns. We use our results to construct semi-orthogonal decompositions for flag varieties over arbitrary bases. This generalises a result of Kapranov.

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Ajneet Dhillon, Sayantan Roy Chowdhury. 2024-05-01. Semiorthogonal decompositions for generalized Severi-Brauer schemes. https://arxiv.org/abs/2405.00580

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