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arXiv · 2607.01178

Sheared Witt Vectors

Bhargav Bhatt·Akhil Mathew·Vadim Vologodsky
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Abstract

V. Drinfeld and E. Lau introduced a ``decompletion'' of the ring of $p$-typical Witt vectors, following earlier work of T. Zink. The goal of this paper is to offer an exposition of this construction, which we call the sheared Witt vectors, on the category of rings $R$ whose reduction is a perfect $\mathbb{F}_p$-algebra.

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Bhargav Bhatt, Akhil Mathew, Vadim Vologodsky. 2026-07-01. Sheared Witt Vectors. https://arxiv.org/abs/2607.01178

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