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arXiv · 2407.21327

Fontaine-Laffaille Theory over Power Series Rings

Christian Hokaj
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Abstract

Let $k$ be a perfect field of characteristic $p > 2$. We extend the equivalence of categories between Fontaine-Laffaille modules and $\mathbb{Z}_p$ lattices inside crystalline representations with Hodge-Tate weights at most $p-2$ of Fontaine and Laffaille to the situation where the base ring is the power series ring over the Witt vectors $ W(k)[\![ t_1, \cdots , t_d]\!]$ and where the base ring is a $p$-adically complete ring that is \'etale over the Tate Algebra $W(k)\langle t_1^{\pm 1}, \cdots , t_d^{\pm 1}\rangle$.

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Christian Hokaj. 2024-07-31. Fontaine-Laffaille Theory over Power Series Rings. https://arxiv.org/abs/2407.21327

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