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Related papers: A generalization of $\varkappa$-metrizable spaces

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This note is devoted to proving the following result: given a compact metrizable group G, there is a compact metric space K such that G is isomorphic (as a topological group) to the isometry group of K.

Group Theory · Mathematics 2007-05-23 Julien Melleray

We show the existence of Lipschitz-free spaces verifying the Point of Continuity Property with arbitrarily high weak-fragmentability index. For this purpose, we use a generalized construction of the countably branching diamond graphs. As a…

Functional Analysis · Mathematics 2025-04-25 Estelle Basset

This paper concerns the self-similarity of topological spaces, in the sense defined in math.DS/0411344. I show how to recognize self-similar spaces, or more precisely, universal solutions of self-similarity systems. Examples include the…

Dynamical Systems · Mathematics 2007-05-23 Tom Leinster

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

We prove that the Lipschitz-free space over a countable compact metric space is isometric to a dual space and has the metric approximation property.

Functional Analysis · Mathematics 2014-04-16 Aude Dalet

For a cardinal $\kappa > \omega$ a metric space $X$ is called to be $\kappa$-superuniversal whenever for every metric space $Y$ with $|Y| < \kappa$ every partial isometry from a subset of $Y$ into $X$ can be extended over the whole space…

General Topology · Mathematics 2014-07-15 Wojciech Bielas

A topological space $G$ is said to be a {\it rectifiable space} provided that there are a surjective homeomorphism $\phi :G\times G\rightarrow G\times G$ and an element $e\in G$ such that $\pi_{1}\circ \phi =\pi_{1}$ and for every $x\in G$…

General Topology · Mathematics 2012-03-06 Fucai Lin

A topological space $X$ is said to be {\em $Y$-rigid} if any continuous map $f:X\rightarrow Y$ is constant. In this paper we construct a number of examples of regular countably compact $\mathbb R$-rigid spaces with additional properties…

General Topology · Mathematics 2021-10-11 Serhii Bardyla , Lyubomyr Zdomskyy

In \cite{Chaber}, Chaber has proved that countably compact spaces with a quasi $G_{\delta }$-diagonal are compact. We prove that initially $\kappa $% -compact spaces with a quasi $G_{\kappa }$-diagonal are compact, for any infinite cardinal…

General Topology · Mathematics 2017-05-02 Çetin Vural

We obtain some classification result for the mapping class groups of compact orientable surfaces in terms of measure equivalence. In particular, the mapping class groups of different closed surfaces can not be measure equivalent. Moreover,…

Group Theory · Mathematics 2018-10-31 Yoshikata Kida

We prove that every vertically nearly separately continuous function defined on a product of a strong PP-space and a topological space and with values in a strongly $\sigma$-metrizable space with a special stratification, is a pointwise…

General Topology · Mathematics 2014-07-23 Olena Karlova

An $\omega_1$-compact space is a space in which every closed discrete subspace is countable. We give various general conditions under which a locally compact, $\omega_1$-compact space is $\sigma$-countably compact, i.e., the union of…

General Topology · Mathematics 2022-06-07 Peter Nyikos , Lyubomyr Zdomskyy

In this paper a generalization of Urysohn's metrization theorem is given for higher cardinals. Namely, it is shown that a topological space with a basis of cardinality at most $|\omega_\mu|$ or smaller is $\omega_\mu$-metrizable if and only…

General Topology · Mathematics 2011-05-24 Joonas Ilmavirta

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

In this paper, some features of countably $\alpha$-compact topological spaces are presented and proven. The connection between countably $\alpha$% -compact, Tychonoff, and $\alpha$-Hausdorff spaces is explained. The space is countably…

General Topology · Mathematics 2022-05-25 Eman Almuhur , Muhammad Ahsan Khan

The strong shape category of compact metrizable spaces (compacta) is very well-studied; extending it to noncompact spaces, however, introduces computational complexity that makes it hard to work with. The fine shape category, as defined by…

Algebraic Topology · Mathematics 2025-10-14 Vladislav Zemlyanoy

In this note we prove that a regular continuous open image of the Sorgenfrey line with an uncountable weight has a closed subspace that is homeomorphic to the Sorgenfrey line. As a corollary we deduce the theorem in the title.

General Topology · Mathematics 2021-10-26 Vlad Smolin

We construct a new compactification of the moduli space H_g of smooth hyperelliptic curves of genus g. We compare our compactification with other well-known remarkable compactifications of H_g .

Algebraic Geometry · Mathematics 2007-06-13 Marco Pacini

We investigate conditions under which a co-computably enumerable closed set in a computable metric space is computable and prove that in each locally computable computable metric space each co-computably enumerable compact manifold with…

Logic in Computer Science · Computer Science 2015-07-01 Zvonko Iljazovic

The property of countable metacompactness of a topological space gets its importance from Dowker's 1951 theorem that the product of a normal space X with the unit interval is again normal iff X is countably metacompact. In a recent paper,…

Logic · Mathematics 2024-05-29 Rodrigo Carvalho , Tanmay Inamdar , Assaf Rinot