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arXiv · 1601.05939

On wild extensions of a p-adic field

I. Del Corso·R. Dvornicich·M. Monge
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Abstract

In this paper we consider the problem of classifying the isomorphism classes of extensions of degree pk of a p-adic field, restricting to the case of extensions without intermediate fields. We establish a correspondence between the isomorphism classes of these extensions and some Kummer extensions of a suitable field F containing K. We then describe such classes in terms of the representations of Gal(F/K). Finally, for k = 2 and for each possible Galois group G, we count the number of isomorphism classes of the extensions whose normal closure has a Galois group isomorphic to G. As a byproduct, we get the total number of isomorphism classes.

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I. Del Corso, R. Dvornicich, M. Monge. 2016-01-22. On wild extensions of a p-adic field. https://doi.org/10.1016/j.jnt.2016.10.006

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