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Related papers: Definable compactness in o-minimal structures

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A compact space $X$ is said to be minimal if there exists a map $f:X\to X$ such that the forward orbit of any point is dense in $X$. We consider rigid minimal spaces, motivated by recent results of Downarowicz, Snoha, and Tywoniuk [J. Dyn.…

Dynamical Systems · Mathematics 2020-02-13 J. P. Boroński , Jernej Činč , Magdalena Foryś-Krawiec

We initiate an investigation of structures on the set of real numbers having the property that path components of definable sets are definable. All o\nobreakdash-\hspace{0pt}minimal structures on $(\mathbb{R},<)$ have the property, as do…

We give a definition of compactness in L-fuzzy topological spaces and provide a characterization of compact L-fuzzy topological spaces, where L is a complete quasi-monoidal lattice with some additional structures, and we present a version…

General Topology · Mathematics 2010-10-26 Joaquin Luna-Torres , Elias Salazar-Buelvas

This paper has two parts. In the first one, we prove that an invariant dp-minimal type is either finitely satisfiable or definable. We also prove that a definable version of the (p,q)-theorem holds in dp-minimal theories of small or medium…

Logic · Mathematics 2015-09-24 Pierre Simon

Every bounded definable open set is a union of finitely many open strong cells in a weakly o-minimal expansion of a real closed field. We prove this fact and another theorem similar to it.

Logic · Mathematics 2026-02-23 Tomohiro Kawakami , Hiroshi Tanaka

We generalize two of our previous results on abelian definable groups in $p$-adically closed fields to the non-abelian case. First, we show that if $G$ is a definable group that is not definably compact, then $G$ has a one-dimensional…

Logic · Mathematics 2024-02-06 Will Johnson , Ningyuan Yao

We propose a definition of computable manifold by introducing computability as a structure that we impose to a given topological manifold, just in the same way as differentiability or piecewise linearity are defined for smooth and PL…

Logic in Computer Science · Computer Science 2017-03-16 Marcelo A. Aguilar , Rodolfo Conde

We show that, for a certain large class of power-bounded $o$-minimal $\mathcal{L}_T$-theories $T$ whose field of exponents is infinite-dimensional as a vector space over the rationals, any definable set in a $T$-convex valued field…

Logic · Mathematics 2018-12-11 Yimu Yin

We give a notion of Scott rank for separable metric structures based on the definability of the (metric closures of) automorphism orbits in continuous infinitary logic. This is a continuous analogue of work of Montalb\'an for countable…

Logic · Mathematics 2024-11-05 Diego Bejarano

Compact sets in constructive mathematics capture our intuition of what computable subsets of the plane (or any other complete metric space) ought to be. A good representation of compact sets provides an efficient means of creating and…

Logic in Computer Science · Computer Science 2010-08-04 Russell O'Connor

We introduce the Hausdorff measure for definable sets in an o-minimal structure, and prove the Cauchy-Crofton and co-area formulae for the o-minimal Hausdorff measure. We also prove that every definable set can be partitioned into "basic…

Logic · Mathematics 2021-11-23 Antongiulio Fornasiero , Elisa Vasquez Rifo

Let $K \subset {\mathbb R}^n$ be a compact definable set in an o-minimal structure over $\mathbb R$, e.g., a semi-algebraic or a subanalytic set. A definable family $\{ S_\delta|\> 0< \delta \in {\mathbb R} \}$ of compact subsets of $K$, is…

Algebraic Geometry · Mathematics 2017-05-17 Saugata Basu , Andrei Gabrielov , Nicolai Vorobjov

We revisit the definition of effective local compactness, and propose an approach that works for arbitrary countably-based spaces extending the previous work on computable metric spaces. We use this to show that effective local compactness…

Logic in Computer Science · Computer Science 2019-03-14 Arno Pauly

The main purpose is to establish two theorems about closed 0-definable subsets $A$ of an affine space $K^{n}$ over a Hensel minimal field $K$. The first, being a non-Archimedean counterpart of one from o-minimal geometry, states that every…

Logic · Mathematics 2026-04-14 Krzysztof Jan Nowak

We provide a complete classification of the possible cofinal structures of the families of precompact (totally bounded) sets in general metric spaces, and compact sets in general complete metric spaces. Using this classification, we…

General Topology · Mathematics 2017-01-04 Aviv Eshed , M. Vincenta Ferrer , Salvador Hernández , Piotr Szewczak , Boaz Tsaban

Some new classes of compacta $K$ are considered for which $C(K)$ endowed with the pointwise topology has a countable cover by sets of small local norm--diameter.

Functional Analysis · Mathematics 2015-10-20 Wiesław Kubiś , Aníbal Moltó , Stanimir Troyanski

We investigate continuous functions definable in a definably complete uniformly locally o-minimal expansion of the second kind of a densely linearly ordered abelian group (DCULOAS structure). We prove a variant of the Arzela-Ascoli theorem…

Logic · Mathematics 2021-02-04 Masato Fujita

We present a definable smooth version of the Thom transversality theorem. We show further that the set of non-transverse definable smooth maps is nowhere dense in the definable smooth topology. Finally, we prove a definable version of a…

Differential Geometry · Mathematics 2020-04-29 Nhan Nguyen , Saurabh Trivedi

A topological space is almost locally compact if it contains a dense locally compact subspace. We generalize a result from \cite{Ma}, showing that isomorphism on Borel classes of almost locally compact Polish metric structures is always…

Logic · Mathematics 2025-08-12 Maciej Malicki

We develop the theory of locally small spaces in a new simple language and apply this simplification to re-build the theory of locally definable spaces over structures with topologies.

General Topology · Mathematics 2020-09-08 Artur Piękosz
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