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arXiv · 2406.02922

Saturated de Rham-Witt complexes with unit-root coefficients

Ravi Fernando
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Abstract

The saturated de Rham-Witt complex, introduced by Bhatt-Lurie-Mathew, is a variant of the classical de Rham-Witt complex which provides a conceptual simplification of the construction and which is expected to produce better results for non-smooth varieties. In this paper, we introduce a generalization of the saturated de Rham-Witt complex which allows coefficients in a unit-root $F$-crystal. We define our complex by a universal property in a category of so-called de Rham-Witt modules. We prove a number of results about it, including existence, quasicoherence, and comparisons to the de Rham-Witt complex of Bhatt-Lurie-Mathew and (in the smooth case) to crystalline cohomology and the classical de Rham-Witt complex with coefficients.

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Ravi Fernando. 2024-06-05. Saturated de Rham-Witt complexes with unit-root coefficients. https://arxiv.org/abs/2406.02922

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