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Related papers: Open cell property in weakly o-minimal structures

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We prove several structural results on definably compact groups G in o-minimal expansions of real closed fields, such as (i) G is definably an almost direct product of a semisimple group and a commutative group, and (ii) the group (G, .) is…

Logic · Mathematics 2008-11-04 Ehud Hrushovski , Ya'acov Peterzil , Anand Pillay

We use the Cauchy-Crofton formula to show that every definable cell (bounded by a ball with rational radius) in an O-minimal expansion of a field extension of the real numbers satisfies the Whitney arc property.

Logic · Mathematics 2010-11-09 Elisa Vasquez Rifo

We present a diagram surveying equivalence or strict implication for properties of different nature (algebraic, model theoretic, topological, etc.) about groups definable in o-minimal structures. All results are well-known and an extensive…

Logic · Mathematics 2020-10-29 Annalisa Conversano

Through careful analysis of types inspired by [AGTW21] we characterize a notion of definable compactness for definable topologies in general o-minimal structures, generalizing results from [PP07] about closed and bounded definable sets in…

Logic · Mathematics 2021-11-09 Pablo Andújar Guerrero

We prove that any definable family of subsets of a definable infinite set $A$ in an o-minimal structure has cardinality at most $|A|$. We derive some consequences in terms of counting definable types and existence of definable topological…

Logic · Mathematics 2023-06-05 Pablo Andújar Guerrero

We develop a general ring theory in the o-minimal setting culminating in a description of all the definable rings in an arbitrary o-minimal structure. We show that every definably connected ring with non-trivial multiplication defines an…

Logic · Mathematics 2025-03-05 Annalisa Conversano

We show that certain families of sets in $\mathbb{R}^2$ (or $\mathbb{R}^n$) which are neither definable nor have bounded VC-dimension are nonetheless uniformly approximately definable in the real field, an o-minimal structure.

Logic · Mathematics 2026-05-12 Leonardo N. Coregliano , Maryanthe Malliaris

Dense pairs of geometric topological fields have tame open core, that is, every definable open subset in the pair is already definable in the reduct. We fix a minor gap in the published version of van den Dries's seminal work on dense pairs…

Logic · Mathematics 2019-11-13 Elías Baro , Amador Martín-Pizarro

We establish the first global results for groups definable in tame expansions of o-minimal structures. Let $\mathcal N$ be an expansion of an o-minimal structure $\mathcal M$ that admits a good dimension theory. The setting includes dense…

Logic · Mathematics 2018-07-20 Pantelis E. Eleftheriou

Given a structure $\mathcal{M}$ with a definable topology, its open core is a structure defined on the same universe whose language consists of all open sets of all arities definable in $\mathcal{M}$. In response to questions raised by…

Logic · Mathematics 2026-05-14 Alexi Block Gorman , Esther Elbaz Saban

We consider locally o-minimal structures possessing tame topological properties shared by models of DCTC and uniformly locally o-minimal expansions of the second kind of densely linearly ordered abelian groups. We derive basic properties of…

Logic · Mathematics 2023-02-22 Masato Fujita

Arguments on PL,(=piecewise linear) topology work over any ordered field in the same way as over the real field, and those on differential topology do over a real closed field R in an o-minimal structure that expands (R,<,0,1,+,cdot). One…

Logic · Mathematics 2010-02-17 Masahiro Shiota

In this paper we give an explicit characterization of o-minimal structures with definable Skolem functions/definable choice. Such structures are, after naming finitely many elements from the prime model, a union of finitely many trivial…

Logic · Mathematics 2022-07-26 Bruno Dinis , Mário J. Edmundo

We demonstrate the following uniform local definable cell decomposition theorem in this paper. Consider a structure $\mathcal M = (M, <,0,+, \ldots)$ elementarily equivalent to a locally o-minimal expansion of the group of reals $(\mathbb…

Logic · Mathematics 2019-12-13 Masato Fujita

Let X be a definable sub-set of some o-minimal structure. We study the spectrum of X, in relation with the definability of types.

Logic · Mathematics 2007-05-23 Antongiulio Fornasiero

We study directed sets definable in o-minimal structures, showing that in expansions of ordered fields these admit cofinal definable curves, as well as a suitable analogue in expansions of ordered groups, and furthermore that no analogue…

Logic · Mathematics 2021-09-17 Pablo Andujar Guerrero , Margaret E. M. Thomas , Erik Walsberg

Given an o-minimal structure ${\mathcal M}$ with a group operation, we show that for a properly convex subset $U$, the theory of the expanded structure ${\mathcal M}'=({\mathcal M},U)$ has definable Skolem functions precisely when…

Logic · Mathematics 2016-11-17 Michael C. Laskowski , Christopher S. Shaw

This paper addresses some questions about dimension theory for P-minimal structures. We show that, for any definable set A, the dimension of the frontier of A is strictly smaller than the dimension of A itself, and that A has a…

Logic · Mathematics 2015-09-01 Pablo Cubides-Kovacsics , Luck Darnière , Eva Leenknegt

In this paper we prove tight bounds on the combinatorial and topological complexity of sets defined in terms of $n$ definable sets belonging to some fixed definable family of sets in an o-minimal structure. This generalizes the…

Combinatorics · Mathematics 2014-02-26 Saugata Basu

We present a relatively simple description of binary, definable subsets of models of weakly quasi-o-minimal theories. In particular, we closely describe definable linear orders and prove a weak version of the monotonicity theorem. We also…

Logic · Mathematics 2021-06-01 Slavko Moconja , Predrag Tanović