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20002026
most citedDefinable henselian valuations

2 citations · 8 across the 10 of their papers we have counts for

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math.NT2026

The Galois characterisation of -adically closed fields -- A modern perspective

Leo Gitin, Jochen Koenigsmann, Benedikt Stock

In 1927, Artin and Schreier showed that a field is real closed if and only if its absolute Galois group has order two. Inspired by this characterisation and drawing on earlier work…

math.NT2022

An elementary proof of the local Kronecker-Weber theorem

Jochen Koenigsmann, Benedikt Stock

We will present a novel elementary, self-contained, and explicit proof of the local Kronecker-Weber theorem. Apart from discrete valuation theory, it does not make use of any tools…

math.NT2015★ 1 cited

Recovering p-adic valuations from pro-p Galois groups

Jochen Koenigsmann, Kristian Strommen

Let be a field with , where denotes the maximal pro-2 quotient of the absolute Galois group of a field . We prove that then adm…

math.NT2013

Undecidability in number theory

Jochen Koenigsmann

These lecture notes cover classical undecidability results in number theory, Hilbert's 10th problem and recent developments around it, also for rings other than the integers. It al…

math.NT2010

Defining in

Jochen Koenigsmann

We show that is definable in by a universal first-order formula in the language of rings. We also present an -formula for …

math.NT2000★ 1 cited

Relatively projective groups as absolute Galois groups

Jochen Koenigsmann

By two well-known results, one of Ax, one of Lubotzky and van den Dries, a profinite group is projective iff it is isomorphic to the absolute Galois group of a pseudo-algebraically…