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Related papers: The model theory of separably tame valued fields

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We show that the K-theory cosheaf is a complete invariant for separable continuous fields with vanishing boundary maps over a finite-dimensional compact metrizable topological space whose fibers are stable Kirchberg algebras with rational…

Operator Algebras · Mathematics 2014-02-12 Rasmus Bentmann

We investigate the computability-theoretic properties of valued fields, and in particular algebraically closed valued fields and $p$-adically closed valued fields. We give an effectiveness condition, related to Hensel's lemma, on a valued…

Logic · Mathematics 2017-09-29 Matthew Harrison-Trainor

Assume that $(L,v)$ is a finite Galois extension of a valued field $(K,v)$. We give an explicit construction of the valuation ring $\mathcal O_L$ of $L$ as an $\mathcal O_K$-algebra, and an explicit description of the module of relative…

Commutative Algebra · Mathematics 2025-06-18 Steven Dale Cutkosky , Franz-Viktor Kuhlmann

The main purpose of the paper is to establish a closedness theorem over Henselian valued fields $K$ of equicharacteristic zero (not necessarily algebraically closed) with separated analytic structure. It says that every projection with a…

Algebraic Geometry · Mathematics 2018-01-09 Krzysztof Jan Nowak

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 show that separably closed valued fields of finite imperfection degree (either with lambda-functions or commuting Hasse derivations) eliminate imaginaries in the geometric language. We then use this classification of interpretable sets…

Logic · Mathematics 2018-02-14 Martin Hils , Moshe Kamensky , Silvain Rideau

Given a field extension $F/C$, the ``Lambda closure'' $\Lambda_{F}C$ of $C$ in $F$ is a subextension of $F/C$ that is minimal with respect to inclusion such that $F/\Lambda_{F}C$ is separable. The existence and uniqueness of $\Lambda_{F}C$…

Logic · Mathematics 2025-05-13 Sylvy Anscombe

Let $K$ be a Henselian, non-trivially valued field with separated analytic structure. We prove the existence of definable retractions onto an arbitrary closed definable subset of $K^{n}$. Hence directly follow definable non-Archimedean…

Algebraic Geometry · Mathematics 2019-02-01 Krzysztof Jan Nowak

A finite \'etale map between irreducible, normal varieties is called tame, if it is tamely ramified with respect to all partial compactifications whose boundary is the support of a strict normal crossings divisor. We prove that if the…

Algebraic Geometry · Mathematics 2016-06-29 Lars Kindler

We conjecture that a $p$-algebra over a complete discrete valued field $K$ contains a totally ramified purely inseparable subfield if and only if it contains a totally ramified cyclic maximal subfield. We prove the conjecture in several…

Rings and Algebras · Mathematics 2024-02-19 Adam Chapman , S. Srimathy

Let $\mathcal M=\langle K;O\rangle$ be a real closed valued field and let $k$ be its residue field. We prove that every interpretable field in $\mathcal M$ is definably isomorphic to either $K$, $K(\sqrt{-1})$, $k$, or $k(\sqrt{-1})$. The…

Logic · Mathematics 2021-05-11 Assaf Hasson , Ya'acov Peterzil

We study in detail the valuation theory of deeply ramified fields and introduce and investigate several other related classes of valued fields. Further, a classification of defect extensions of prime degree of valued fields that was earlier…

Commutative Algebra · Mathematics 2023-01-12 Franz-Viktor Kuhlmann , Anna Rzepka

For a finite totally ramified extension $L$ of a complete discrete valuation field $K$ with the perfect residue field of characteristic $p>0$, it is known that $L/K$ is an abelian extension if the upper ramification breaks are integers and…

Number Theory · Mathematics 2025-04-15 Taichi Inoue

We prove that for p-optimal fields (a very large subclass of p-minimal fields containing all the known examples) a cell decomposition theorem follows from methods going back to Denef's paper [Invent. Math, 77 (1984)]. We derive from it the…

Logic · Mathematics 2016-02-08 Luck Darnière , Immanuel Halupczok

We give a function field specific, algebraic proof of the main results of class field theory for abelian extensions of degree coprime to the characteristic. By adapting some methods known for number fields and combining them in a new way,…

Number Theory · Mathematics 2015-12-03 Florian Hess , Maike Massierer

In this article we study definable functions in tame expansions of algebraically closed valued fields. For a given definable function we have two types of results: of type (I), which hold at a neighborhood of infinity, and of type (II),…

Logic · Mathematics 2018-02-12 Pablo Cubides Kovacsics , Françoise Delon

For a quasi-projective scheme $X$ admitting a smooth compactification over a local field of residue characteristic $p > 0$, we construct a continuous reciprocity homomorphism from a tame class group to the abelian tame etale fundamental…

Algebraic Geometry · Mathematics 2026-01-21 Rahul Gupta , Amalendu Krishna , Jitendra Rathore

We investigate the model completeness of the theory of a mixed characteristic henselian valued field with finite ramification relative to the residue field and value group. We address the case in which the valued field has a value group…

Logic · Mathematics 2024-04-05 Anna De Mase

We show that asymptotic (valued differential) fields have unique maximal immediate extensions. Connecting this to differential-henselianity, we prove that any differential-henselian asymptotic field is differential-algebraically maximal,…

Commutative Algebra · Mathematics 2020-12-09 Nigel Pynn-Coates

We previously obtained a generalization and refinement of results about the ramification theory of Artin-Schreier extensions of discretely valued fields in characteristic $p$ with perfect residue fields to the case of fields with more…

Number Theory · Mathematics 2017-07-07 Vaidehee Thatte