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arXiv · 1201.5973

Explicitly Extending Frobenius Splittings over Finite Maps

Karl Schwede·Kevin Tucker
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Abstract

Suppose that $π\: Y \to X$ is a finite map of normal varieties over a perfect field of characteristic $p > 0$. Previous work of the authors gave a criterion for when Frobenius splittings on $X$ (or more generally any $p^{-e}$-linear map) extend to $Y$. In this paper we give an alternate and highly explicit proof of this criterion (checking term by term) when $π$ is tamely ramified in codimension 1. Some additional examples are also explored.

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Karl Schwede, Kevin Tucker. 2012-01-28. Explicitly Extending Frobenius Splittings over Finite Maps. https://arxiv.org/abs/1201.5973

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