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arXiv · 1905.10495

Canonical lifts and $\delta$-structures

James Borger·Lance Gurney
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Abstract

We extend the Serre-Tate theory of canonical lifts of ordinary abelian varieties to arbitrary unpolarised families of ordinary abelian varieties parameterised by a $p$-adic formal scheme $S$. We show that the canonical lift is the unique lift to $W(S)$ which admits a $\delta$-structure in the sense of Joyal, Buium, and Bousfield. We prove analogous statements for families of ordinary $p$-groups and $p$-divisible groups.

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James Borger, Lance Gurney. 2019-05-25. Canonical lifts and $\delta$-structures. https://arxiv.org/abs/1905.10495

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