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arXiv · 2207.10382

Canonical Witt formal scheme extensions and p-torsion groups

Alessandra Bertapelle·Nicola Mazzari·Arnab Saha
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Abstract

We study the $n$-th arithmetic jet space of the $p$-torsion subgroup attached to a smooth commutative formal group scheme. We show that the $n$-th jet space above fits in the middle of a canonical short exact sequence between a power of the formal scheme of Witt vectors of length $n$ and the $p$-torsion subgroup we started with. This result generalizes a result of Buium on roots of unity.

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Alessandra Bertapelle, Nicola Mazzari, Arnab Saha. 2022-07-21. Canonical Witt formal scheme extensions and p-torsion groups. https://doi.org/10.1007/s10231-023-01321-2

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