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arXiv · 1607.08590

Purely log terminal threefolds with non-normal centres in characteristic two

Paolo Cascini·Hiromu Tanaka
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Abstract

We show that many classical results of the minimal model programme do not hold over an algebraically closed field of characteristic two. Indeed, we construct a three dimensional plt pair whose codimension one part is not normal, a three dimensional klt singularity which is not rational nor Cohen-Macaulay, and a klt Fano threefold with non-trivial intermediate cohomology.

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Paolo Cascini, Hiromu Tanaka. 2016-07-28. Purely log terminal threefolds with non-normal centres in characteristic two. https://arxiv.org/abs/1607.08590

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