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arXiv · 2102.02788

Global Frobenius Liftability II: Surfaces and Fano Threefolds

Piotr Achinger·Jakub Witaszek·Maciej Zdanowicz
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Abstract

In this article, a sequel to "Global Frobenius Liftability I" (math:1708:03777v2), we continue the development of a comprehensive theory of Frobenius liftings modulo $p^2$. We study compatibility of divisors and closed subschemes with Frobenius liftings, Frobenius liftings of blow-ups, descent under quotients by some group actions, stability under base change, and the properties of associated F-splittings. Consequently, we characterise Frobenius liftable surfaces and Fano threefolds, confirming the conjecture stated in our previous paper.

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Piotr Achinger, Jakub Witaszek, Maciej Zdanowicz. 2021-02-04. Global Frobenius Liftability II: Surfaces and Fano Threefolds. https://arxiv.org/abs/2102.02788

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