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On the vanishing of Tor of the absolute integral closure

Hans Schoutens
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Abstract

Let $R$ be an excellent local domain of positive characteristic with residue field $k$ and let $R^+$ be its absolute integral closure. If $\text{Tor}^R_1(R^+,k)$ vanishes, then $R$ is Cohen-Macaulay, normal, F-rational and F-pure. If $R$ has at most an isolated singularity or has dimension at most two, then $R$ is regular.

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Hans Schoutens. 2003-04-03. On the vanishing of Tor of the absolute integral closure. https://arxiv.org/abs/math/0304051

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