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arXiv · 1508.06787

Incarnations of Berthelot's conjecture

Christopher Lazda
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Abstract

In this article we give a survey of the various forms of Berthelot's conjecture and some of the implications between them. By proving some comparison results between pushforwards of overconvergent isocrystals and those of arithmetic $\mathcal{D}$-modules, we manage to deduce some cases of the conjecture from Caro's results on the stability of overcoherence under pushforward via a smooth and proper morphism of varieties. In particular, we show that Ogus' convergent pushforward of an overconvergent $F$-isocrystal under a smooth and projective morphism is overconvergent.

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Christopher Lazda. 2015-08-27. Incarnations of Berthelot's conjecture. https://doi.org/10.1016/j.jnt.2016.02.028

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