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Related papers: Hurewicz sets of reals without perfect subsets

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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

Whereas the Gerlits-Nagy gamma-property is strictly weaker than the Galvin-Miller strong gamma-property, the corresponding strong notions for the Menger, Hurewicz, Rothberger, Gerlits-Nagy (*), Arkhangel'skii and Sakai properties are…

Logic · Mathematics 2010-08-02 Boaz Tsaban

We investigate products of sets of reals with combinatorial covering properties. A topological space satisfies $\mathsf{S}_1(\Gamma,\Gamma)$ if for each sequence of point-cofinite open covers of the space, one can pick one element from each…

General Topology · Mathematics 2019-12-06 Piotr Szewczak , Magdalena Włudecka

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…

General Topology · Mathematics 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…

General Topology · Mathematics 2007-12-10 Liljana Babinkostova

W. Hurewicz proved that analytic Menger sets of reals are $\sigma$-compact and that co-analytic completely Baire sets of reals are completely metrizable. It is natural to try to generalize these theorems to projective sets. This has…

General Topology · Mathematics 2018-03-12 Franklin D. Tall , Lyubomyr Zdomskyy

We study the preservation of selective covering properties, including classic ones introduced by Menger, Hurewicz, Rothberger, Gerlits and Nagy, and others, under products with some major families of concentrated sets of reals. Our methods…

General Topology · Mathematics 2014-02-18 Arnold W. Miller , Boaz Tsaban , Lyubomyr Zdomskyy

In this paper we show that it is relatively consistent with ZFC that every gamma-set is countable while not every strong measure zero set is countable. This answers a question of Paul Szeptycki. A set is a gamma-set iff every omega-cover…

Logic · Mathematics 2007-05-23 Arnold W. Miller

Hindman's celebrated Finite Sums Theorem, and its high-dimensional version due to Milliken and Taylor, are extended from covers of countable sets to covers of arbitrary topological spaces with Menger's classic covering property. The methods…

General Topology · Mathematics 2017-11-09 Boaz Tsaban

In this paper, we continue to investigate topological properties of $\mathcal{I}H$ and its two star versions namely $SS \mathcal{I} H$ and $S \mathcal{I} H$. We characterized $\mathcal{I}$-Hurewicz property by $\mathcal{I}$-Hurewicz Basis…

General Topology · Mathematics 2019-10-31 Manoj Bhardwaj , B. K. Tyagi

We prove that the Hurewicz property is not preserved by finite products in the Miller model. This is a consequence of the fact that Miller forcing preserves ground model $\gamma$-spaces.

General Topology · Mathematics 2019-09-18 Dušan Repovš , 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…

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

Let S1(Gamma,Gamma) be the statement: For each sequence of point-cofinite open covers, one can pick one element from each cover and obtain a point-cofinite cover. b is the minimal cardinality of a set of reals not satisfying…

General Topology · Mathematics 2010-11-05 Arnold W. Miller , Boaz Tsaban

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 discuss ways of adjoining perfect sets of mutually generic random reals. In particular, we show that if V \sub W are models of ZFC and W contains a dominating real over V, then W[r], where r is random over W, contains a perfect tree of…

Logic · Mathematics 2016-09-06 Jörg Brendle

We solve the last standing open problem from the seminal paper by J. Gerlits and Zs. Nagy, which was later reposed by A. Miller, T. Orenshtein and B. Tsaban. Namely, we show that under p = c there is a \delta-set that is not a \gamma-set.…

General Topology · Mathematics 2023-05-15 Serhii Bardyla , Jaroslav Supina , Lyubomyr Zdomskyy

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 describe the second homotopy group of any CW-complex $K$ by analyzing the universal cover of a locally finite model of $K$ using the notion of $G$-coloring of a partially ordered set. As applications we prove a generalization of the…

Algebraic Topology · Mathematics 2014-12-18 Jonathan Ariel Barmak , Elias Gabriel Minian

For a Tychonoff space $X$, we denote by $C_p(X)$ the space of all real-valued continuous functions on $X$ with the topology of pointwise convergence. We give the functional characterization of the covering property of Hurewicz.

General Topology · Mathematics 2018-05-31 Alexander V. Osipov

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…

Logic · Mathematics 2010-11-02 Boaz Tsaban , Lyubomyr Zdomskyy