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相关论文: A diagonalization property between Hurewicz and Me…

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We continue to investigate various diagonalization properties for sequences of open covers of separable metrizable spaces introduced in Part I. These properties generalize classical ones of Rothberger, Menger, Hurewicz, and Gerlits-Nagy. In…

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…

逻辑 · 数学 2010-11-02 Tomek Bartoszynski , Boaz Tsaban

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…

逻辑 · 数学 2010-11-02 Tomek Bartoszynski , Saharon Shelah , Boaz Tsaban

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…

一般拓扑 · 数学 2016-10-27 Piotr Szewczak , 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…

一般拓扑 · 数学 2010-11-02 Boaz Tsaban

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.…

一般拓扑 · 数学 2010-11-02 Boaz Tsaban , Lubomyr Zdomsky

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…

一般拓扑 · 数学 2017-12-12 Dušan Repovš , Lyubomyr Zdomskyy

We provide new techniques to construct sets of reals without perfect subsets and with the Hurewicz or Menger covering properties. In particular, we show that if the Continuum Hypothesis holds, then there are such sets which can be mapped…

一般拓扑 · 数学 2026-03-02 Piotr Szewczak , Tomasz Weiss , Lyubomyr Zdomskyy

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.

逻辑 · 数学 2007-05-23 Tomek Bartoszynski , Marion Scheepers

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

一般拓扑 · 数学 2018-09-19 Rodrigo Hernández-Gutiérrez , Paul J. Szeptycki

Let $\mathcal{P}$ be a topological property. A.V. Arhangel'skii calls $X$ projectively $\mathcal{P}$ if every second countable continuous image of $X$ is $\mathcal{P}$. Lj.D.R. Ko$\check{c}$inac characterized the classical covering…

一般拓扑 · 数学 2020-05-06 Alexander V. Osipov

In this paper we discuss what kind of constrains combinatorial covering properties of Menger, Scheepers, and Hurewicz impose on remainders of topological groups. For instance, we show that such a remainder is Hurewicz if and only it is…

一般拓扑 · 数学 2016-06-10 Angelo Bella , Seçil Tokgöz , Lyubomyr Zdomskyy

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…

一般拓扑 · 数学 2007-12-10 Liljana Babinkostova

Using a dictionary translating a variety of classical and modern covering properties into combinatorial properties of continuous images, we get a simple way to understand the interrelations between these properties in ZFC and in the realm…

逻辑 · 数学 2010-11-02 Boaz Tsaban , Lyubomyr Zdomskyy

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…

一般拓扑 · 数学 2023-10-05 Maddalena Bonanzinga , Davide Giacopello , Fortunato Maesano

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…

一般拓扑 · 数学 2023-08-22 Christopher Caruvana

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…

逻辑 · 数学 2019-11-13 Lyubomyr Zdomskyy

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…

一般拓扑 · 数学 2023-05-19 Jozef Chaber , Roman Pol

A classical theorem of Hurewicz characterizes spaces with the Hurewicz covering property as those having bounded continuous images in the Baire space. We give a similar characterization for spaces X which have the Hurewicz property…

一般拓扑 · 数学 2014-09-02 Boaz Tsaban , Lyubomyr Zdomskyy

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 :…

一般拓扑 · 数学 2022-02-28 Manoj Bhardwaj , Alexander V. Osipov
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