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arXiv · 1711.09940

Higher displays arising from filtered de Rham-Witt complexes

Abstract

For a smooth projective scheme $X$ over a ring $R$ on which $p$ is nilpotent that meets some general assumptions we prove that the crystalline cohomology is equipped with the structure of a higher display which is a relative version of Fontaine's strongly divisible lattices. Frobenius-divisibilty is induced by the Nygaard filtration on the relative de Rham-Witt complex. For a nilpotent PD-thickening $S/R$ we also consider the associated relative display and can describe it explicitly by a relative version of the Nygaard filtration on the de Rham-Witt complex associated to a lifting of $X$ over $S$. We prove that there is a crystal of relative displays if moreover the mod $p$ reduction of $X$ has a smooth and versal deformation space.

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BibTeXRIS

Oliver Gregory, Andreas Langer. 2020-06-24. Higher displays arising from filtered de Rham-Witt complexes. https://arxiv.org/abs/1711.09940

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