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We prove that many completeness properties coincide in metric spaces, precompact groups and dense subgroups of products of separable metric groups. We apply these results to function spaces C_p(X,G) of G-valued continuous functions on a…

General Topology · Mathematics 2017-05-26 Alejandro Dorantes-Aldama , Dmitri Shakhmatov

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

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

The countable uniform power (or uniform box product) of a uniform space $X$ is a special topology on ${}^{\omega}X$ that lies between the Tychonoff topology and the box topology. We solve an open problem posed by P. Nyikos showing that if…

General Topology · Mathematics 2018-09-20 Rodrigo Hernández-Gutiérrez , Paul J. Szeptycki

we prove that if $X$ is a locally compact $\sigma$-compact space then on its quotient, $\gamma(X)$ say, determined by the algebra of all real valued bounded continuous functions on $X$, the quotient topology and the completely regular…

General Topology · Mathematics 2008-11-21 Aldo J. Lazar

The main result of this article is: THEOREM. Every homogeneous locally conical connected separable metric space that is not a $1$-manifold is strongly $n$-homogeneous for each $n \geq 2$ and countable dense homogeneous. Furthermore,…

General Topology · Mathematics 2017-06-02 Fredric D. Ancel , David P. Bellamy

We prove that assuming $\mathfrak{b}=\mathfrak{d}$, in the class of hereditarily Lindel\"of spaces, each productively Scheepers space is productively Hurewicz. The above statement remains true in the class of all general topological spaces…

General Topology · Mathematics 2026-02-19 Marta Kładź-Duda , Piotr Szewczak , Lyubomyr Zdomskyy

Motivated by the main results of the articles by Hattori and Bouziad, we seek to answer the following questions about Hattori spaces. Let A be a subset of the real line, then: Given a compact set $K$ in the Euclidean topology, under what…

General Topology · Mathematics 2023-09-21 Elmer Enrique Tovar-Acosta

A topological space $X$ is strongly $D$ if for any neighbourhood assignment $\{U_x:x\in X\}$, there is a $D\subseteq X$ such that $\{U_x:x\in D\}$ covers $X$ and $D$ is locally finite in the topology generated by $\{U_x:x\in X\}$. We prove…

General Topology · Mathematics 2019-02-19 Daniel T. Soukup , Paul J. Szeptycki

Assume that $\mathcal{P}$ is a topological property of a space $X$, then we say that $X$ is {\it dense-$\mathcal{P}$} if each dense subset of $X$ has the property $\mathcal{P}$. In this paper, we mainly discuss dense subsets of a space $X$,…

General Topology · Mathematics 2023-04-10 Fucai Lin , Qiyun Wu

A dual pair formulation for asymmetric locally convex spaces is developed that strictly generalises the ordinary vector space setting. The concept of a polar topology carries over to the asymmetric case and some familiar results are…

General Topology · Mathematics 2026-02-24 Jobst Ziebell

In a recent paper \cite{T} the fact that a class of locally compact metric spaces $X$, among which are Euclidean spaces, are not homemorphic to their punctured version $X\men\{p\}$, was given an interesting new proof which does not use…

General Topology · Mathematics 2023-08-08 Giuseppe De Marco

The class of spaces such that their product with every Lindel\"of space is Lindel\"of is not well-understood. We prove a number of new results concerning such productively Lindel\"of spaces with some extra property, mainly assuming the…

General Topology · Mathematics 2011-04-12 Franklin D. Tall , Boaz Tsaban

We give a construction under $CH$ of a non-metrizable compact Hausdorff space $K$ such that any uncountable semi-biorthogonal sequence in $C(K)$ must be of a very specific kind. The space $K$ has many nice properties, such as being…

General Topology · Mathematics 2009-11-03 MIrna Dzamonja , Istvan Juhasz

We show that it is consistent that for some uncountable cardinal k, all compactifications of the countable discrete space with remainders homeomorphic to $D^k$ are homeomorphic to each other. On the other hand, there are $2^c$ pairwise…

General Topology · Mathematics 2007-05-23 Mikhail Matveev

An old question of A.V. Arhangel'skii asks if the Menger property of a Tychonoff space $X$ is preserved by homeomorphisms of its function space $C_p(X)$. We provide affirmative answer in the case of linear homeomorphisms. To this end, we…

General Topology · Mathematics 2023-11-27 Mikołaj Krupski

We show that it is consistent relative to a weakly compact cardinal that strong homology is additive and compactly supported within the class of locally compact separable metric spaces. This complements work of Marde\v{s}i\'{c} and Prasolov…

Logic · Mathematics 2022-02-22 Nathaniel Bannister , Jeffrey Bergfalk , Justin Tatch Moore

A space $X$ is called selectively separable(R-separable) if for every sequence of dense subspaces $(D_n : n\in\omega)$ one can pick finite (respectively, one-point) subsets $F_n\subset D_n$ such that $\bigcup_{n\in\omega}F_n$ is dense in…

General Topology · Mathematics 2011-12-09 Angelo Bella , Mikhail Matveev , Santi Spadaro

For an index set $\Gamma$ and a cardinal number $\kappa$ the $\Sigma_{\kappa}$-product of real lines $\Sigma_{\kappa}(\mathbb{R}^{\Gamma})$ consist of all elements of $\mathbb{R}^{\Gamma}$ with $<\kappa$ nonzero coordinates. A compact space…

General Topology · Mathematics 2024-07-08 Krzysztof Zakrzewski

We characterize H-spaces which are p-torsion Postnikov pieces of finite type by a cohomological property together with a necessary acyclicity condition. When the mod p cohomology of an H-space is finitely generated as an algebra over the…

Algebraic Topology · Mathematics 2007-05-23 Natalia Castellana , Juan A. Crespo , Jerome Scherer