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arXiv · 1611.08529

The reduction of $G$-ordinary crystalline representations with $G$-structure

Macarena Peche Irissarry
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Abstract

Fontaine's $D_{\mathrm{cris}}$ functor allow us to associate an isocrystal to any crystalline representation. For a reductive group $G$, we study the reduction of lattices inside a germ of crystalline representations with $G$-structure $V$ to lattices (which are crystals) with $G$-structure inside $D_{\mathrm{cris}}(V)$. Using Kisin modules theory, we give a description of this reduction in terms of $G$, in the case when the representation $V$ is ($G$-)ordinary. In order to do that, first we need to generalize Fargues' construction of the Harder-Narasimhan filtration for $p$-divisible groups to Kisin modules.

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Macarena Peche Irissarry. 2016-11-25. The reduction of $G$-ordinary crystalline representations with $G$-structure. https://arxiv.org/abs/1611.08529

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