The paper continues a series of papers devoted to study of the connection between two approaches to classification of complete discrete valuation fields with imperfect residue fields and, in particular, 2-dimensional local fields in the case of mixed characteristic. One of these approaches was introduced by Masato Kurihara (1987) in terms of the module of differentials. Another one is based on Epp’s theory of elimination of wild ramification. A lower bound for the degree of a constant field extension that makes a given field into an almost standard one is established. This bound is expressed in terms of the invariant introduced in Kurihara’s paper.
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Dedicated to the 80th jubilee of A. V. Yakovlev
Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 492, 2020, pp. 25–44.
Translated by I. Ponomarenko.
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Vostokov, S.V., Zhukov, I.B. & Ivanova, O.Y. Kurihara Invariants and Elimination of Wild Ramification. J Math Sci 264, 15–28 (2022). https://doi.org/10.1007/s10958-022-05974-x
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DOI: https://doi.org/10.1007/s10958-022-05974-x