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arXiv · 1007.3094

Ramification correspondence of finite flat group schemes over equal and mixed characteristic local fields

Shin Hattori
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Abstract

Let p>2 be a rational prime, k be a perfect field of characteristic p and K be a finite totally ramified extension of the fractional field of the Witt ring of k. Let G and H be finite flat commutative group schemes killed by p over O_K and k[[u]], respectively. In this paper, we show the upper and the lower ramification subgroups of G and H in the sense of Abbes-Saito are naturally isomorphic to each other when they are associated to the same Kisin module.

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Shin Hattori. 2012-05-17. Ramification correspondence of finite flat group schemes over equal and mixed characteristic local fields. https://doi.org/10.1016/j.jnt.2012.04.003

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