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arXiv · 2007.13810

Compatible ideals in Gorenstein rings

Thomas Polstra·Karl Schwede
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Abstract

Suppose $R$ is a $\mathbb{Q}$-Gorenstein $F$-finite and $F$-pure ring of prime characteristic $p>0$. We show that if $I\subseteq R$ is a compatible ideal (with all $p^{-e}$-linear maps) then there exists a module finite extension $R\to S$ such that the ideal $I$ is the sum of images of all $R$-linear maps $S\to R$.

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Thomas Polstra, Karl Schwede. 2022-11-07. Compatible ideals in Gorenstein rings. https://arxiv.org/abs/2007.13810

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