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arXiv · 1008.0305

Overconvergent Witt Vectors

Christopher Davis·Andreas Langer·Thomas Zink
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Abstract

Let A be a finitely generated algebra over a field K of characteristic p >0. We introduce a subring of the ring of Witt vectors W(A). We call it the ring of overconvergent Witt vectors. We prove that on a scheme X of finite type over K the overconvergent Witt vectors are an \'etale sheaf. In a forthcoming paper (Annales ENS) we define an overconvergent de Rham-Witt complex on a smooth scheme X over a perfect field K whose hypercohomology is the rigid cohomology of X in the sense of Berthelot.

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Christopher Davis, Andreas Langer, Thomas Zink. 2010-08-02. Overconvergent Witt Vectors. https://arxiv.org/abs/1008.0305

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