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Related papers: Property A for coarse spaces

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We introduce the group-compact coarse structure on a Hausdorff topological group in the context of coarse structures on an abstract group which are compatible with the group operations. We develop asymptotic dimension theory for the…

Geometric Topology · Mathematics 2012-01-24 Andrew Nicas , David Rosenthal

We discuss a set-valued generalization of strong proximinality in Banach spaces, introduced by J. Mach [Continuity properties of Chebyshev centers, J. Approx. Theory, 29(3):223--230, 1980] as property-$(P_1)$. We establish that if the…

Functional Analysis · Mathematics 2022-03-29 Teena Thomas

We give a survey of the known connections between regularity conditions and amenability conditions in the setting of uniform algebras. For a uniform algebra $A$ we consider the set, $A_{lc}$, of functions in $A$ which are locally constant…

Functional Analysis · Mathematics 2014-12-25 M. J. Heath , J. F. Feinstein

We investigate possible quantifications of the Dunford-Pettis property. We show, in particular, that the Dunford-Pettis property is automatically quantitative in a sense. Further, there are two incomparable mutually dual stronger versions…

Functional Analysis · Mathematics 2013-02-27 Miroslav Kačena , Ondřej F. K. Kalenda , Jiří Spurný

In this paper we examine two basic topological properties of partial metric spaces, namely compactness and completeness. Our main result claims that in these spaces compactness is equivalent to sequential compactness. We also show that…

General Topology · Mathematics 2022-02-01 Dariusz Bugajewski , Piotr Maćkowiak , Ruidong Wang

Let $\mathfrak{M}$ be a class of metric spaces. A metric space $Y$ is minimal $\mathfrak{M}$-universal if every $X\in\mathfrak{M}$ can be isometrically embedded in $Y$ but there are no proper subsets of $Y$ satisfying this property. We find…

Metric Geometry · Mathematics 2015-04-17 V. Bilet , O. Dovgoshey , M. Kucukaslan , E. Petrov

Countably infinite groups (with a fixed underlying set) constitute a Polish space $G$ with a suitable metric, hence the Baire category theorem holds in $G$. We study isomorphism invariant subsets of $G$, which we call group properties. We…

We study the properties of topological spaces $(X,\tau)$, where $X$ is a definable set in an o-minimal structure and the topology $\tau$ on $X$ has a basis that is (uniformly) definable. Examples of such spaces include the canonical…

Logic · Mathematics 2023-10-11 Pablo Andújar Guerrero , Margaret E. M. Thomas

Uniformity and proximity are two different ways for defining small scale structures on a set. Coarse structures are large scale counterparts of uniform structures. In this paper, motivated by the definition of proximity, we develop the…

Geometric Topology · Mathematics 2021-11-12 Sh. Kalantari , B. Honari

John Roe \cite{Roe lectures} introduced coarse structures for arbitrary sets $X$ by considering subsets of $X\times X$. That definition, while natural for analysts, is a bit more difficult to digest for topologists and geometers. In this…

Metric Geometry · Mathematics 2007-05-23 J. Dydak , C. S. Hoffland

A new sequential approach to investigations of structure of metric spaces at infinity is proposed. Criteria for finiteness and boundedness of metric spaces at infinity are found.

Metric Geometry · Mathematics 2017-04-04 Viktoriia Bilet , Oleksiy Dovgoshey

We consider asymptotic dimension of coarse spaces. We analyse coarse structures induced by metrisable compactifications. We calculate asymptotic dimension of coarse cell complexes. We calculate the asymptotic dimension of certain negatively…

Metric Geometry · Mathematics 2007-05-23 Bernd Grave

Brodskiy, Dydak, LaBuz, and Mitra introduced the concepts of uniform joinability and local uniform joinability for uniform spaces when developing their theory of generalized uniform covering maps which was motivated by a paper by…

General Mathematics · Mathematics 2021-01-20 Brendon LaBuz

Property~(A) is a week symmetry condition that plays a fundamental role in the characterization of greedy-type bases in the isometric case, i.e., when the constants involved in the study of the efficiency of the thresholding greedy…

Functional Analysis · Mathematics 2024-09-10 Fernando Albiac , Jose L. Ansorena , Pablo Berná , Miguel Berasategui

We study countable embedding-universal and homomorphism-universal structures and unify results related to both of these notions. We show that many universal and ultrahomogeneous structures allow a concise description (called here a finite…

Combinatorics · Mathematics 2010-09-06 Jan Hubicka

We introduce and investigate a quantitative version of Steinhaus' property $(S)$ for Banach spaces, called the uniform property $(S)$. A Banach space $X$ is said to have uniform $(S)$ if for every pair of distinct unit vectors $x,y\in X$…

Functional Analysis · Mathematics 2026-02-11 William B. Johnson , Tomasz Kania

We construct an example of a coarse proximity space that is not induced by any coarse structure. We then show how to "stitch" two coarse proximity spaces with homeomorphic boundaries into one coarse proximity space. Finally, we construct a…

General Topology · Mathematics 2019-04-26 Pawel Grzegrzolka , Jeremy Siegert

A uniform Roe corona is the quotient of the uniform Roe algebra of a metric space by the ideal of compact operators. Among other results, we show that it is consistent with ZFC that isomorphism between uniform Roe coronas implies coarse…

Operator Algebras · Mathematics 2021-06-18 Bruno de Mendonça Braga , Ilijas Farah , Alessandro Vignati

In this project we explore the geometry of general metric spaces, where we do not necessarily have the tools of differential geometry on our side. Some metric spaces $(X,d)$ allow us to define geodesics, permitting us to compare geodesic…

Metric Geometry · Mathematics 2026-05-22 Søren Poulsen

Isaak Moiseevich Yaglom deduced complete classification of geometric spaces. In this work, supposed to your attention, author formalizes Yaglom's approach and constructs uniform theory of geometric spaces on analytic level. Among its…

Metric Geometry · Mathematics 2018-07-31 Alexander Popa