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This article is devoted to the interplay between productively Menger and productively Hurewicz subspaces of the Cantor space. In particular, we show that in the Laver model for the consistency of the Borel's conjecture these two notions…

General Topology · Mathematics 2025-07-16 Dušan D. Repovš , Lyubomyr Zdomskyy

For a Tychonoff space $X$ and a family $\lambda$ of subsets of $X$, we denote by $C_{\lambda}(X)$ the space of all real-valued continuous functions on $X$ with the set-open topology. In this paper, we study the Menger and projective Menger…

General Topology · Mathematics 2018-03-28 Alexander V. Osipov

We continue to investigate applications of $k$-covers in function spaces with the compact-open topology.

General Topology · Mathematics 2018-05-14 Alexander V. Osipov

My work with Anatoly Vershik concerned automorphism groups of the Rado graph and homeomorphism groups of the Urysohn space. This paper contains some further thoughts on these issues, together with connections to topologies and filters on…

Group Theory · Mathematics 2026-02-27 Peter J. Cameron

We characterize the Hurewicz covering property in metrizable spaces in terms of properties of the metrics of the space. Then we show that a weak version of selective screenability, when combined with the Hurewicz property, implies selective…

General Topology · Mathematics 2007-12-10 Liljana Babinkostova

We introduce a class of proper posets which is preserved under countable support iterations, includes $\omega^\omega$-bounding, Cohen, Miller, and Mathias posets associated to filters with the Hurewicz covering properties, and has the…

Logic · Mathematics 2022-10-21 Dušan Repovš , Lyubomyr Zdomskyy

The open well-filtered spaces were introduced by Shen, Xi, Xu and Zhao to answer the problem whether every core-compact well-filtered space is sober. In the current paper we explore further properties of open well-filtered spaces. One of…

General Topology · Mathematics 2025-02-25 Chong Shen , Xiaoyong Xi , Dongsheng Zhao

Using iterated Sacks forcing and topological games, we prove that the existence of a totally imperfect Menger set in the Cantor cube with cardinality continuum is independent from ZFC. We also analyze the structure of Hurewicz and consonant…

Logic · Mathematics 2025-10-28 Valentin Haberl , Piotr Szewczak , Lyubomyr Zdomskyy

In this thesis, we introduce the subject of D-spaces and some of its most important open problems which are related to well known covering properties. We then introduce a new approach for studying D-spaces and covering properties in…

General Topology · Mathematics 2025-04-17 Talal Alrawajfeh , Hasan Z. Hdeib

This article is devoted to the interplay between forcing with fusion and combinatorial covering properties. We discuss known instances of this interplay as well as present a new one, namely that in the Laver model for the consistency of the…

Logic · Mathematics 2019-11-13 Lyubomyr Zdomskyy

We study the monomorphisms in the category LSpFi of spaces with Lindel\"{o}f Filters. We extend the criterion derived by R. Ball and A. Hager in "Monomorphisms in Spaces with Lindel\"{o}f Filters", Czech. Math.J. 57, No.1 (2007) 281-317.…

General Topology · Mathematics 2014-12-08 Vasil S. Gochev

A space $X$ is said to have the set star Hurewicz property if for each nonempty subset $A$ of $X$ and each sequence $(\mathcal{U}_n: n \in \mathbb{N})$ of sets open in $X$ such that for each $n\in \mathbb N$, $\overline{A} \subset \cup…

General Topology · Mathematics 2020-11-02 Sumit Singh , Ljubisa D. R. Kocinac

We study various combinatorial properties, and the implications between them, for filters generated by infinite-dimensional subspaces of a countable vector space. These properties are analogous to selectivity for ultrafilters on the natural…

Logic · Mathematics 2024-07-22 Iian B. Smythe

We consider ``meager analogues'' of classical covering properties of Menger, Hurewicz and Rothberger. We show that Borel images of sets having ``our'' covering properties have these classical covering properties.

Logic · Mathematics 2007-05-23 Tomek Bartoszynski , Marion Scheepers

We study Hurewicz fibrations between finite T$_0$--spaces from a combinatorial viewpoint and give strong conditions that a continuous map between finite T$_0$--spaces must satisfy in order to be a Hurewicz fibration. We also show that there…

Algebraic Topology · Mathematics 2019-07-10 Nicolás Cianci , Miguel Ottina

We examine the selective screenability property in topological groups. In the metrizable case we also give characterizations in terms of the Haver property and finitary Haver property respectively relative to left-invariant metrics. We…

General Topology · Mathematics 2008-01-09 Liljana Babinkostova

We give several topological/combinatorial conditions that, for a filter on $\omega$, are equivalent to being a non-meager $\mathsf{P}$-filter. In particular, we show that a filter is countable dense homogeneous if and only if it is a…

General Topology · Mathematics 2014-10-07 Kenneth Kunen , Andrea Medini , Lyubomyr Zdomskyy

We construct several topological groups with very strong combinatorial properties. In particular, we give simple examples of subgroups of the real line R (thus strictly o-bounded) which have the Hurewicz property but are not sigma-compact,…

General Topology · Mathematics 2010-11-02 Boaz Tsaban

In this note, we characterize when the Vietoris space of compact subsets of a given space has the Hurewicz property in terms of a selection principle on the given space itself using $k$-covers and the notion of groupability introduced by…

General Topology · Mathematics 2023-08-22 Christopher Caruvana

We consider products of sets of reals with a combinatorial structure based on scales parameterized by filters. This kind of sets were intensively investigated in products of spaces with combinatorial covering properties as Hurewicz,…

Combinatorics · Mathematics 2025-03-28 Michał Pawlikowski , Piotr Szewczak , Lyubomyr Zdomskyy