On Abhyankar's lemma about ramification indices

2018/05/22 by Chabert, Jean-Luc, Halberstadt, Emmanuel
#11R32 #FOS: Mathematics #Number Theory (math.NT)

paper · doi:10.48550/arxiv.1805.08869

Abstract

We provide a simple proof of the fact that the ramification index of the compositum of two finite extensions of local fields is equal to the least common multiple of the ramification indices when at least one of the extensions is tamely ramified.

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