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arXiv · 1507.08517

Tannakian properties of unit Frobenius-modules

Maxim Mornev
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Abstract

We show that unit $\mathcal{O}_{F,X}^Λ$-modules of Emerton and Kisin provide an analogue of locally constant sheaves in the context of Böckle-Pink $Λ$-crystals. For example they form a tannakian category if the coefficient algebra $Λ$ is a field. Our results hold for a big class of coefficien algebras which includes Drinfeld rings, and for arbitary locally noetherian base schemes.

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Maxim Mornev. 2015-08-31. Tannakian properties of unit Frobenius-modules. https://doi.org/10.1016/j.jnt.2016.02.005

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