activity
20002026
most citedDefinable henselian valuations

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

collaborators

13 papers

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.LO2015

Defining coarsenings of valuations

Franziska Jahnke, Jochen Koenigsmann

We study the question which henselian fields admit definable henselian valuations (with or without parameters). We show that every field which admits a henselian valuation with non…

math.LO2014

Uniformly defining -henselian valuations

Franziska Jahnke, Jochen Koenigsmann

Admitting a non-trivial -henselian valuation is a weaker assumption on a field than admitting a non-trivial henselian valuation. Unlike henselianity, -henselianity is an elem…

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…