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Related papers: Definable V-topologies, Henselianity and NIP

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We prove the dp-finite case of the Shelah conjecture on NIP fields. If K is a dp-finite field, then K admits a non-trivial definable henselian valuation ring, unless K is finite, real closed, or algebraically closed. As a consequence, the…

Logic · Mathematics 2020-05-29 Will Johnson

We prove that unstable dp-finite fields admit definable V-topologies. As a consequence, the henselianity conjecture for dp-finite fields implies the Shelah conjecture for dp-finite fields. This gives a conceptually simpler proof of the…

Logic · Mathematics 2020-05-01 Will Johnson

Let $K$ be an NIP field and let $v$ be a henselian valuation on $K$. We ask whether $(K,v)$ is NIP as a valued field. By a result of Shelah, we know that if $v$ is externally definable, then $(K,v)$ is NIP. Using the definability of the…

Logic · Mathematics 2019-12-17 Franziska Jahnke

We study the algebraic implications of the non-independence property (NIP) and variants thereof (dp-minimality) on infinite fields, motivated by the conjecture that all such fields which are neither real closed nor separably closed admit a…

Logic · Mathematics 2018-12-05 Katharina Dupont , Assaf Hasson , Salma Kuhlmann

In this paper, we characterize NIP henselian valued fields modulo the theory of their residue field, both in an algebraic and in a model-theoretic way. Assuming the conjecture that every infinite NIP field is either separably closed, real…

Logic · Mathematics 2024-03-14 Sylvy Anscombe , Franziska Jahnke

We prove that definable ring topologies on NIP fields are closely connected to NIP integral domains. More precisely, we show that up to elementary equivalence, any NIP topological field arises from an NIP integral domain. As an application,…

Logic · Mathematics 2025-04-16 Will Johnson

We show that any theory of tame henselian valued fields is NIP if and only if the theory of its residue field and the theory of its value group are NIP. Moreover, we show that if $(K,v)$ is a henselian valued field of residue characteristic…

Logic · Mathematics 2019-04-03 Franziska Jahnke , Pierre Simon

We show that dp-minimal valued fields are henselian and that a dp-minimal field admitting a definable type V topology is either real closed, algebraically closed or admits a non-trivial definable henselian valuation. We give classifications…

Logic · Mathematics 2015-07-15 Franziska Jahnke , Pierre Simon , Erik Walsberg

The following conjecture is due to Shelah-Hasson: Any infinite strongly NIP field is either real closed, algebraically closed, or admits a non-trivial definable henselian valuation, in the language of rings. We specialise this conjecture to…

Logic · Mathematics 2022-07-04 Lothar Sebastian Krapp , Salma Kuhlmann , Gabriel Lehéricy

We investigate what henselian valuations on ordered fields are definable in the language of ordered rings. This leads towards a systematic study of the class of ordered fields which are dense in their real closure. Some results have…

Logic · Mathematics 2019-02-06 Lothar Sebastian Krapp , Salma Kuhlmann , Gabriel Lehéricy

We prove that NIP valued fields of positive characteristic are henselian. Furthermore, we partially generalize the known results on dp-minimal fields to dp-finite fields. We prove a dichotomy: if K is a sufficiently saturated dp-finite…

Logic · Mathematics 2020-01-16 Will Johnson

In this note we study sets of NIP formulas in some theories of fields and valued fields, with a special focus on the sets of quantifier-free and existential formulas. First, we give a new proof of the fact that Separably Closed Valued…

Logic · Mathematics 2026-02-04 Paulo Andrés Soto Moreno

We give an explicit algebraic characterisation of all definable henselian valuations on a dp-minimal real field. Additionally we characterise all dp-minimal real fields that admit a definable henselian valuation with real closed residue…

Logic · Mathematics 2024-10-15 Lothar Sebastian Krapp , Salma Kuhlmann , Lasse Vogel

Admitting a non-trivial $p$-henselian valuation is a weaker assumption on a field than admitting a non-trivial henselian valuation. Unlike henselianity, $p$-henselianity is an elementary property in the language of rings. We are interested…

Logic · Mathematics 2014-11-26 Franziska Jahnke , Jochen Koenigsmann

We are concerned with topology of Hensel minimal structures on non-trivially valued fields $K$, whose axiomatic theory was introduced in a recent paper by Cluckers-Halupczok-Rideau. We additionally require that every definable subset in the…

Algebraic Geometry · Mathematics 2024-12-10 Krzysztof Jan Nowak

We continue our earlier investigation of dp-finite fields. We show that the "heavy sets" of [6] are exactly the sets of full dp-rank. As a consequence, full dp-rank is a definable property in definable families of sets. If $I$ is the group…

Logic · Mathematics 2019-10-18 Will Johnson

We firstly show that due to their resplendency ordered henselian valued fields admit relative field quantifier elimination in the Denef--Pas language expanded by linear orders in the field and residue field sort. Secondly, we deduce from a…

Logic · Mathematics 2026-04-13 Lothar Sebastian Krapp , Floris Vermeulen

We give explicit formulas witnessing IP, \IPn or TP2 in fields with Artin-Schreier extensions. We use them to control $p$-extensions of mixed characteristic henselian valued fields, allowing us most notably to generalize to the \NIPn…

Logic · Mathematics 2024-09-20 Blaise Boissonneau

This paper is a sequel to [1] and considers definability in differential-henselian monotone fields with c-map and angular component map. We prove an Equivalence Theorem among whose consequences are a relative quantifier reduction and an NIP…

Logic · Mathematics 2018-06-11 Tigran Hakobyan

A field $K$ in a ring language $\mathcal{L}$ is finitely undecidable if $\mbox{Cons}(\Sigma)$ is undecidable for every nonempty finite $\Sigma \subseteq \mbox{Th}(K; \mathcal{L})$. We extend a construction of Ziegler and (among other…

Logic · Mathematics 2023-07-21 Brian Tyrrell
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