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arXiv · 2207.01142

Higher direct images of snc ideal sheaves

Charles Godfrey
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Abstract

We prove invariance results for the cohomology groups of ideal sheaves of simple normal crossing divisors under (a restricted class of) birational morphisms of pairs in arbitrary characteristic, assuming a conjecture regarding the existence of normal Cohen-Macaulayfications. As an application, we extend some foundational results in the theory of rational pairs that were previously known only in characteristic 0.

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Charles Godfrey. 2022-07-03. Higher direct images of snc ideal sheaves. https://arxiv.org/abs/2207.01142

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