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arXiv · 2002.04661

A theorem about maximal Cohen-Macaulay modules

Thomas Polstra
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Abstract

It is shown in a local strongly $F$-regular ring there exits natural number $e_0$ so that if $M$ is any finitely generated maximal Cohen-Macaulay module then the pushforward of $M$ under the $e_0$th iterate of the Frobenius endomorphism contains a free summand. Consequently, the torsion subgroup of the divisor class group of a local strongly $F$-regular ring is finite.

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Thomas Polstra. 2020-02-11. A theorem about maximal Cohen-Macaulay modules. https://arxiv.org/abs/2002.04661

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