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arXiv · 2501.02783

Measuring rationality of Schwede--Takagi pairs

Pat Lank·Peter McDonald·Sridhar Venkatesh
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Abstract

We begin by giving a derived characterization of rational singularities for pairs in the sense of Schwede--Takagi. This characterization extends a characterization of rational singularities due to Lank--Venkatesh to pairs on normal varieties over fields of characteristic zero. As an application, we introduce a categorical invariant that measures the failure of rationality for pairs on affine varieties that are locally complete intersections.

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Pat Lank, Peter McDonald, Sridhar Venkatesh. 2025-01-06. Measuring rationality of Schwede--Takagi pairs. https://arxiv.org/abs/2501.02783

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