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Related papers: The combinatorics of open covers (II)

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In classical works, Hurewicz and Menger introduced two diagonalization properties for sequences of open covers. Hurewicz found a combinatorial characterization of these notions in terms of continuous images. Recently, Scheepers has shown…

General Topology · Mathematics 2010-08-03 Boaz Tsaban

According to a result of Kocinac and Scheepers, the Hurewicz covering property is equivalent to a somewhat simpler selection property: For each sequence of large open covers of the space one can choose finitely many elements from each cover…

General Topology · Mathematics 2010-11-02 Boaz Tsaban

We consider the question, which of the major classes defined by topological diagonalizations of open or Borel covers is hereditary. Many of the classes in the open case are not hereditary already in ZFC, and none of them is provably…

Logic · Mathematics 2010-11-02 Tomek Bartoszynski , Boaz Tsaban

We study the relation between the Hurewicz and Menger properties of filters considered topologically as subspaces of P(\omega) with the Cantor set topology.

General Topology · Mathematics 2018-09-19 Rodrigo Hernández-Gutiérrez , Paul J. Szeptycki

This article is a continuation of the study of bornological open covers and related selection principles in metric spaces done in (Chandra et al. 2020) using the idea of strong uniform convergence (Beer and Levi, 2009) on bornology. Here we…

General Topology · Mathematics 2020-06-03 Debraj Chandra , Pratulananda Das , Subhankar Das

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

This article is devoted to the interplay between forcing with fusion and combinatorial covering properties. We illustrate this interplay by proving that in the Laver model for the consistency of the Borel's conjecture, the product of any…

General Topology · Mathematics 2017-12-12 Dušan Repovš , Lyubomyr Zdomskyy

Motivated by the minimal tower problem, an earlier work studied diagonalizations of covers where the covers are related to linear quasiorders (tau-covers). We deal with two types of combinatorial questions which arise from this study. 1.…

Logic · Mathematics 2010-11-02 Saharon Shelah , Boaz Tsaban

In this paper we consider some recent relative versions of Menger property called set strongly star Menger and set star Menger properties and the corresponding Hurewicz-type properties. In particular, using \cite {BMae}, we "easily" prove…

General Topology · Mathematics 2023-10-05 Maddalena Bonanzinga , Davide Giacopello , Fortunato Maesano

We answer a question of Just, Miller, Scheepers and Szeptycki whether certain diagonalization properties for sequences of open covers are provably closed under taking finite or countable unions. This is a very concise paper. For a…

Logic · Mathematics 2010-11-02 Tomek Bartoszynski , Saharon Shelah , 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 provide simplified solutions of Menger's and Hurewicz's problems and conjectures, concerning generalizations of sigma-compactness. The reader who is new to this field will find a self-contained treatment in Sections 1, 2, and 5. Sections…

General Topology · Mathematics 2017-03-10 Boaz Tsaban

The theorem we prove is a slight strengthening of some results by Just, Miller, Scheepers and Szeptycki [JMSS]. We use the Michael technique instead of the combinatorial approach in the literature. Comments by the submitter: This short…

General Topology · Mathematics 2023-05-19 Jozef Chaber , Roman Pol

We construct Menger subsets of the real line whose product is not Menger in the plane. In contrast to earlier constructions, our approach is purely combinatorial. The set theoretic hypothesis used in our construction is far milder than…

General Topology · Mathematics 2016-10-27 Piotr Szewczak , Boaz Tsaban

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

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 develop the semifilter approach to the classical Menger and Hurewicz covering properties and show that the small cardinal g is a lower bound of the additivity number of the family of Menger subspaces of the Baire space, and under u< g…

General Topology · Mathematics 2007-05-23 Lubomyr Zdomsky

We provide new results on combinatorial characterizations of covering properties in end spaces and ray spaces. In particular, we characterize the Lindel\"of degree, the extent, the Rothberger property, $\sigma$-compactness and the Menger…

Combinatorics · Mathematics 2026-01-21 Rodrigo Rey Carvalho , Matheus Duzi , Vinicius de Oliveira Rodrigues

Menger's basis property is a generalization of $\sigma$-compactness and admits an elegant combinatorial interpretation. We introduce a general combinatorial method to construct non $\sigma$-compact sets of reals with Menger's property.…

General Topology · Mathematics 2010-11-02 Boaz Tsaban , Lubomyr Zdomsky

In this paper, we introduced the mildly version of the Hurewicz basis covering property, studied by Babinkostova, Ko\v{c}inac, and Scheepers. A space $X$ is said to have mildly-Hurewicz property if for each sequence $\langle \mathcal{U}_n :…

General Topology · Mathematics 2022-02-28 Manoj Bhardwaj , Alexander V. Osipov
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