Witt vectors and truncation posets

Vigleik Angeltveit

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arXiv · 1409.4156

Witt vectors and truncation posets

Vigleik Angeltveit

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Abstract

One way to define Witt vectors starts with a truncation poset $S \subset \mathbb{N}$. We generalize Witt vectors to truncation posets, and show how three types of maps of truncation posets can be used to encode the following six structure maps on Witt vectors: addition, multiplication, restriction, Frobenius, Verschiebung and norm.

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Vigleik Angeltveit. 2017-02-08. Witt vectors and truncation posets. https://arxiv.org/abs/1409.4156

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