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Related papers: A Note on Monotonically Metacompact Spaces

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A topological space $X$ is called strongly $\sigma$-metrizable if $X=\bigcup_{n\in\omega}X_n$ for an increasing sequence $(X_n)_{n\in\omega}$ of closed metrizable subspaces such that every convergence sequence in $X$ is contained in some…

General Topology · Mathematics 2016-11-17 Taras Banakh

By a recent result of Juh\'{a}sz and van Mill, a locally compact topological group whose dense subspaces are all separable is metrizable. In this note we investigate the following question: is every locally compact group having all dense…

Group Theory · Mathematics 2024-12-16 Dekui Peng

We study topological properties of random metric spaces which arise by Lambda-coalescents. These are stochastic processes, which start with an infinite number of lines and evolve through multiple mergers in an exchangeable setting. We show…

Probability · Mathematics 2011-05-13 Holger F. Biehler , Peter Pfaffelhuber

A topological space is iso-dense if it has a dense set of isolated points. A topological space is scattered if each of its non-empty subspaces has an isolated point. In $\mathbf{ZF}$, in the absence of the axiom of choice, basic properties…

General Topology · Mathematics 2021-01-11 Kyriakos Keremedis , Eleftherios Tachtsis , Eliza Wajch

A coarse space $X$, endowed with a linear order compatible with the coarse structure of $X$, is called linearly ordered. We prove that every linearly ordered coarse space $X$ is locally convex and the asymptotic dimension of $X$ is either…

General Topology · Mathematics 2021-10-05 Igor Protasov

Metrizable spaces are studied in which every closed set is an $\alpha$-limit set for some continuous map and some point. It is shown that this property is enjoyed by every space containing sufficiently many arcs (formalized in the notion of…

Dynamical Systems · Mathematics 2022-02-14 Jana Hantáková , Samuel Roth , Ľubomír Snoha

We introduce the space of relative orders on a group and show that it is compact whenever the group is finitely generated. We use this to show that if $G$ is a finitely generated group acting by order preserving homeomorphism of on the…

Group Theory · Mathematics 2018-06-12 Yago Antolín , Cristóbal Rivas

A space is od-compact (resp. od-Lindel\"of) provided any cover by open dense sets has a finite (resp. countable) subcover. We first show with simple examples that these properties behave quite poorly under finite or countable unions. We…

General Topology · Mathematics 2015-03-24 Mathieu Baillif

We mainly discuss the cardinal invariants and generalized metric properties on paratopological groups or rectifiable spaces, and show that: (1) If $A$ and $B$ are $\omega$-narrow subsets of a paratopological group $G$, then $AB$ is…

General Topology · Mathematics 2012-03-06 Fucai Lin , Rongxin Shen

We show a number of undecidable assertions concerning countably compact spaces hold under PFA(S)[S]. We also show the consistency without large cardinals of "every locally compact, perfectly normal space is paracompact".

Logic · Mathematics 2016-07-18 Alan Dow , Franklin D. Tall

A metric space $(M, d)$ is said to be universal for a class of metric spaces if all metric spaces in the class can be isometrically embedded into $(M, d)$. In this paper, for a metrizable space $Z$ possessing abundant subspaces, we first…

Metric Geometry · Mathematics 2024-09-27 Yoshito Ishiki , Katsuhisa Koshino

Locally compact separable metrizable spaces are characterized among all metrizable spaces as those that admit a cofinal sequence $K_1\subset K_2\subset\cdots$ of compact subsets. Their \v{C}ech cohomology is well-understood due to Petkova's…

Geometric Topology · Mathematics 2022-11-21 Sergey A. Melikhov

We prove that the free locally convex space $L(X)$ over a metrizable space $X$ has countable tightness if and only if $X$ is separable.

General Topology · Mathematics 2014-07-08 S. S. Gabriyelyan

We consider a generic class of log-concave, possibly random, (Gibbs) measures. We prove the concentration of an infinite family of order parameters called multioverlaps. Because they completely parametrise the quenched Gibbs measure of the…

Probability · Mathematics 2022-12-22 Jean Barbier , Dmitry Panchenko , Manuel Sáenz

We introduce the property of countable separation for a locally convex Hausdorff space $X$ and relate it to the existence of a metrizable coarser topology. Building on this, we demonstrate how the separability of $X$ is equivalent to the…

Functional Analysis · Mathematics 2025-10-10 Thomas Ruf

We give Ramsey expansions of classes of generalised metric spaces where distances come from a linearly ordered commutative monoid. This complements results of Conant about the extension property for partial automorphisms and extends an…

Combinatorics · Mathematics 2021-07-06 Jan Hubička , Matěj Konečný , Jaroslav Nešetřil

Suppose G is a topological group containing a (closed) topological copy of the Frechet-Urysohn fan. If G is a perfectly normal sequential space (a normal k-space) then every closed metrizable subset in $G$ is locally compact. Applying this…

General Topology · Mathematics 2011-08-23 Taras Banakh

We characterize coset spaces of topological groups which are coset spaces of (separable) metrizable groups and complete metrizable (Polish) groups. Besides, it is shown that for a $G$-space $X$ with a $d$-open action there is a topological…

General Topology · Mathematics 2017-11-29 Sergey Antonyan , Natella Antonyan , Konstantin Kozlov

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

We characterize when the countable power of a Corson compactum has a dense metrizable subspace and construct consistent examples of Corson compacta whose countable power does not have a dense metrizable subspace. We also give several…

General Topology · Mathematics 2024-03-26 Arkady Leiderman , Santi Spadaro , Stevo Todorcevic