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Related papers: First-countable Lindel\"of scattered spaces

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We show that there are uncountably many mutually non-isomorphic Lipschitz-free spaces over countable, complete, discrete metric spaces. Also there is a countable, complete, discrete metric space whose free space does not embed into the free…

Functional Analysis · Mathematics 2025-05-27 Estelle Basset , Gilles Lancien , Antonín Procházka

Work of Linnell shows that the space of left-orderings of a group is either finite or uncountable, and in the case that the space is finite, the isomorphism type of the group is known---it is what is known as a Tararin group. By defining…

Group Theory · Mathematics 2020-10-27 Adam Clay , Idrissa Ba

We show that the topology of pointwise convergence on scattered spaces is compatible with the group structure of their homeomorphism group. We then establish a few topological properties of the homeomorphism group of the first uncountable…

Group Theory · Mathematics 2020-12-02 Maxime Gheysens

We consider the cardinal sequences of compact scattered spaces in models where CH is false. We describe a number of models where the continuum is aleph_2 in which no such space can have aleph_2 countable levels.

General Topology · Mathematics 2007-05-23 Kenneth Kunen

Dimensional types of metric scattered spaces are investigated. Revised proofs of Mazurkiewicz-Sierpi\'nski and Knaster-Urbanik theorems are presented. Embeddable properties of countable metric spaces are generalized onto uncountable metric…

General Topology · Mathematics 2015-05-01 Szymon Plewik , Marta Walczyńska

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

We show that (in ZFC) every infinite set S can be equipped with 2^|S| complete metrics which generate mutually non-homeomorphic scattered order topologies on S. Furthermore, we show that (in ZFC) every uncountable set S can be equipped with…

General Topology · Mathematics 2020-05-20 Gerald Kuba

A space is said to be "almost discretely Lindel\"of" if every discrete subset can be covered by a Lindel\"of subspace. Juh\'asz, Tkachuk and Wilson asked whether every almost discretely Lindel\"of first-countable Hausdorff space has…

General Topology · Mathematics 2017-10-18 Angelo Bella , Santi Spadaro

We investigate the behavior of functional countability and exponential separability in products and subspaces of topological spaces. We solve a problem of Tkachuk by showing that the product of functionally countable pseudocompact spaces is…

General Topology · Mathematics 2026-03-03 Rodrigo Hernández-Gutiérrez , Santi Spadaro

A space $ X $ is said to be set star-Lindel\"{o}f (resp., set strongly star-Lindel\"{o}f) if for each nonempty subset $ A $ of $ X $ and each collection $ \mathcal{U} $ of open sets in $ X $ such that $ \overline{A} \subseteq \bigcup…

General Mathematics · Mathematics 2021-06-30 Sumit Singh

In this paper we study the properties of P-generated spaces (by analogy with compactly generated). We prove that a regular Lindel\"of generated space with uncountable dispersion character is resolvable. It is proved that Hausdorff…

General Topology · Mathematics 2017-12-05 Maria A. Filatova , Alexander V. Osipov

We introduce the notion of echeloned spaces - an order-theoretic abstraction of metric spaces. The first step is to characterize metrizable echeloned spaces. It turns out that morphisms between metrizable echeloned spaces are uniformly…

This article has been withdrawn in 2013. The class of LOTS (linearly ordered topological spaces) contains many important spaces, like the set of real numbers, the set of rational numbers and the ordinals. Such spaces have rich topological…

General Topology · Mathematics 2018-03-29 Kyriakos Papadopoulos

This article initiates the study of topological transcendental fields $\FF$ which are subfields of the topological field $\CC$ of all complex numbers such that $\FF$ consists of only rational numbers and a nonempty set of transcendental…

General Topology · Mathematics 2022-02-03 Taboka Prince Chalebgwa , Sidney A. Morris

We investigate whether an arbitrary base for a dense-in-itself topological space can be partitioned into two bases. We prove that every base for a T_3 Lindel\"of topology can be partitioned into two bases while there exists a consistent…

General Topology · Mathematics 2014-01-27 Daniel T. Soukup , Lajos Soukup

Let $L(X)$ be the free locally convex space over a Tychonoff space $X$. We show that the following assertions are equivalent: (i) $L(X)$ is $\ell_\infty$-barrelled, (ii) $L(X)$ is $\ell_\infty$-quasibarrelled, (iii) $L(X)$ is…

Functional Analysis · Mathematics 2018-10-30 Saak Gabriyelyan

We give a complete classification of mixed Tsirelson spaces T[(F\_i, theta\_i)\_{i=1}^r ] for finitely many pairs of given compact and hereditary families F\_i of finite sets of integers and 0<theta\_i<1 in terms of the Cantor-Bendixson…

Functional Analysis · Mathematics 2007-05-23 Jordi Lopez Abad , Antonis Manoussakis

In this paper, we investigate the poset $\mathbf{OF}(X)$ of free open filters on a given space $X$. In particular, we characterize spaces for which $\mathbf{OF}(X)$ is a lattice. For each $n\in\mathbb{N}$ we construct a scattered space $X$…

General Topology · Mathematics 2024-06-26 Serhii Bardyla , Jaroslav Supina , Lyubomyr Zdomskyy

A linear ordering is called context-free if it is the lexicographic ordering of some context-free language and is called scattered if it has no dense subordering. Each scattered ordering has an associated ordinal, called its rank. It is…

Formal Languages and Automata Theory · Computer Science 2019-07-29 Kitti Gelle , Szabolcs Ivan

We show that if we add any number of Cohen reals to the ground model then, in the generic extension, a locally compact scattered space has at most (2^{aleph_0})^V many levels of size omega. We also give a complete ZFC characterization of…

Logic · Mathematics 2007-05-23 István Juhász , Saharon Shelah , Lajos Soukup , Zoltán Szentmiklóssy