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arXiv · 1405.3861

Ramification estimate for Fontaine-Laffaille Galois modules

Victor Abrashkin
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Abstract

Suppose $K$ is unramified over $\mathbb Q _p$ and $Γ_K=\operatorname{Gal}(\bar K/K)$. Let $H$ be a torsion $Γ_K$-equivariant subquotient of crystalline $\mathbb Q _p[Γ_K]$-module with HT weights from $[0,p-2]$. We give a new proof of Fontaine's conjecture about the triviality of action of some ramification subgroups $Γ_K^{(v)}$ on $H$. The earlier author's proof from [1] contains a gap and proves this conjecture only for some subgroups of index $p$ in $Γ_K^{(v)}$.

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Victor Abrashkin. 2014-05-15. Ramification estimate for Fontaine-Laffaille Galois modules. https://arxiv.org/abs/1405.3861

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