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arXiv · 2308.08118

Elliptic singularities and threefold flops in positive characteristic

Hiromu Tanaka
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Abstract

Let $X$ be a smooth threefold over an algebraically closed field of positive characteristic. We prove that an arbitrary flop of $X$ is smooth. To this end, we study Gorenstein curves of genus one and two-dimensional elliptic singularities defined over imperfect fields.

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Hiromu Tanaka. 2023-08-16. Elliptic singularities and threefold flops in positive characteristic. https://doi.org/10.1017/s0013091525000185

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