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

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We try to explain the differences between the concepts of stratifiable space and $\varkappa$-metrizable space. In particular, we give a characterization of $\varkappa$-metrizable spaces which is modelled on Chigogidze's characterization.…

General Topology · Mathematics 2019-11-25 Wojciech Bielas , Andrzej Kucharski , Szymon Plewik

The aim of this paper is to investigate the class of quasi $\kappa$-metrizable spaces. This class is invariant with respect to arbitrary products and contains Shchepin's $\kappa$-metrizable spaces as a proper subclass.

General Topology · Mathematics 2019-07-03 Vesko Valov

We introduce the notion of compactifiable classes -- these are classes of metrizable compact spaces that can be up to homeomorphic copies ``disjointly combined'' into one metrizable compact space. This is witnessed by so-called compact…

General Topology · Mathematics 2020-02-19 A. Bartoš , J. Bobok , J. van Mill , P. Pyrih , B. Vejnar

We show in ZF that: (i) Every subcompact metrizable space is completely metrizable, and every completely metrizable space is countably subcompact. (ii) A metrizable space X=(X,T) is countably compact iff it is countably subcompact relative…

General Topology · Mathematics 2021-02-23 Kyriakos Keremedis

We show in detail that every compact countable subset of a metric space is homeomorphic to a countable ordinal number, which extends a result given by Mazurkiewicz and Sierpinski for finite-dimensional Euclidean spaces. In order to achieve…

General Topology · Mathematics 2019-11-12 Borys Álvarez-Samaniego , Andrés Merino

A characterization of $\varkappa$-metrizable compacta in terms of extension of functions and usco retractions into superextensions is established.

General Topology · Mathematics 2010-02-20 Vesko Valov

A topological space $X$ is cometrizable if it admits a weaker metrizable topology such that each point $x\in X$ has a (not necessarily open) neighborhood base consisting of metrically closed sets. We study the relation of cometrizable…

General Topology · Mathematics 2020-04-07 Taras Banakh , Yaryna Stelmakh

In this paper we introduce and study so-called $k^*$-metrizable spaces forming a new class of generalized metric spaces, and display various applications of such spaces in topological algebra, functional analysis, and measure theory. By…

General Topology · Mathematics 2011-10-11 T. O. Banakh , V. I. Bogachev , A. V. Kolesnikov

We show that all sufficiently nice $\lambda$-sets are countable dense homogeneous ($\mathsf{CDH}$). From this fact we conclude that for every uncountable cardinal $\kappa \le \mathfrak{b}$ there is a countable dense homogeneous metric space…

General Topology · Mathematics 2018-09-19 Rodrigo Hernández-Gutiérrez , Michael Hrušák , Jan van Mill

For metrizable spaces we replace the notion of almost periodic homeomorphism with a similar notion and verify that the usual characterizations of almost periodic homeomorphisms of compact metric spaces are valid for all metrizable spaces.

Dynamical Systems · Mathematics 2007-05-23 Paul Fabel

Let $P$ be a directed set and $X$ a space. A collection $\mathcal{C}$ of subsets of $X$ is \emph{$P$-locally finite} if $\mathcal{C}=\bigcup \{ \mathcal{C}_p : p \in P\}$ where (i) if $p \le p'$ then $\mathcal{C}_p \subseteq…

General Topology · Mathematics 2015-01-09 Ziqin Feng , Paul Gartside , Jeremiah Morgan

In the work it is shown that the space of idempotent probability measures with compact supports is kappa-metrizable if the given Tychonoff space is kappa-metrizable. It is constructed a series of max-plus-convex subfunctors of the functor…

General Topology · Mathematics 2019-05-23 Azad Yangibayevich Ishmetov

We prove that compact Hausdorff spaces with a $\mathbb{P}$-diagonal are metrizable.

General Topology · Mathematics 2016-09-02 Alan Dow , Klaas Pieter Hart

We prove that each metrizable space (of cardinality less or equal to continuum) has a (first countable) uniform Eberlein compactification and each scattered metrizable space has a scattered hereditarily paracompact compactification. Each…

General Topology · Mathematics 2012-12-19 Taras Banakh , Arkady Leiderman

In a recent paper by D. Shakhmatov and J. Sp\v{e}v\'ak [Group-valued continuous functions with the topology of pointwise convergence, Topology and its Applications (2009), doi:10.1016/j.topol.2009.06.022] the concept of a ${\rm TAP}$ group…

General Topology · Mathematics 2009-12-01 Xabier Domínguez Vaja Tarieladze

Denote by $\mathbf C_p[\mathfrak M_0]$ the $C_p$-stable closure of the class $\mathfrak M_0$ of all separable metrizable spaces, i.e., $\mathbf C_p[\mathfrak M_0]$ is the smallest class of topological spaces that contains $\mathfrak M_0$…

General Topology · Mathematics 2021-11-01 T. Banakh , S. Gabriyelyan

All spaces are assumed to be Tychonoff. Given a realcompact space $X$, we denote by $\mathsf{Exp}(X)$ the smallest infinite cardinal $\kappa$ such that $X$ is homeomorphic to a closed subspace of $\mathbb{R}^\kappa$. Our main result shows…

General Topology · Mathematics 2024-11-20 Claudio Agostini , Andrea Medini , Lyubomyr Zdomskyy

We prove pseudocompactness of a Tychonoff space $X$ and the space $\mathcal{P}(X)$ of Radon probability measures on it with the weak topology under the condition that the Stone-\v{C}ech compactification of the space $\mathcal{P}(X)$ is…

Functional Analysis · Mathematics 2024-03-26 Vladimir I. Bogachev

Hurewicz proved completely metrizable Menger spaces are /sigma-compact. We extend this to Cech-complete Menger spaces and consistently to projective Menger metrizable spaces. On the other hand, it is consistent that there is a co-analytic…

General Topology · Mathematics 2016-07-19 Franklin D. Tall , Secil Tokgoz

The concept of the strong Pytkeev property, recently introduced by Tsaban and Zdomskyy in [32], was successfully applied to the study of the space $C_c(X)$ of all continuous real-valued functions with the compact-open topology on some…

General Topology · Mathematics 2014-12-05 S. S. Gabriyelyan , J. Kakol
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