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arXiv · 2004.03768

Graded quotients of ramification groups of local fields with imperfect residue fields

Takeshi Saito
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Abstract

We prove that the graded quotients of the filtration by ramification groups of any henselian discrete valuation field of residue characteristic $p>0$ are $F_p$-vector spaces. We define an injection of the character group of each graded quotient to a twisted cotangent space defined using a cotangent complex.

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Takeshi Saito. 2020-04-08. Graded quotients of ramification groups of local fields with imperfect residue fields. https://doi.org/10.1353/ajm.2023.a907702

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