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arXiv · 2001.10491

Nash blowups in prime characteristic

Daniel Duarte·Luis Núñez-Betancourt
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Abstract

We initiate the study of Nash blowups in prime characteristic. First, we show that a normal variety is non-singular if and only if its Nash blowup is an isomorphism, extending a theorem by A. Nobile. We also study higher Nash blowups, as defined by T. Yasuda. Specifically, we give a characteristic-free proof of a higher version of Nobile's Theorem for quotient varieties and hypersurfaces. We also prove a weaker version for $F$-pure varieties.

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Daniel Duarte, Luis Núñez-Betancourt. 2020-01-28. Nash blowups in prime characteristic. https://arxiv.org/abs/2001.10491

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