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arXiv · 1112.2383

On the F-purity of isolated log canonical singularities

Osamu Fujino·Shunsuke Takagi
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Abstract

A singularity in characteristic zero is said to be of dense F-pure type if its modulo p reduction is locally F-split for infinitely many p. We prove that if $x \in X$ is an isolated log canonical singularity with $μ(x \in X) \le 2$ (see Definition 1.4 for the definition of the invariant $μ$), then it is of dense F-pure type. As a corollary, we prove the equivalence of log canonicity and being of dense F-pure type in the case of three-dimensional isolated singularities.

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Osamu Fujino, Shunsuke Takagi. 2012-07-02. On the F-purity of isolated log canonical singularities. https://arxiv.org/abs/1112.2383

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