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Related papers: Embeddings into countably compact Hausdorff spaces

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We study hierarchical clusterings of metric spaces that change over time. This is a natural geometric primitive for the analysis of dynamic data sets. Specifically, we introduce and study the problem of finding a temporally coherent…

Data Structures and Algorithms · Computer Science 2017-10-23 Tamal K. Dey , Alfred Rossi , Anastasios Sidiropoulos

Let $(X,\tau)$ be a Hausdorff space, where $X$ is an infinite set. The compact complement topology $\tau^{\star}$ on $X$ is defined by: $\tau^{\star}=\{\emptyset\} \cup \{X\setminus M, \text{where $M$ is compact in $(X,\tau)$}\}$. In this…

General Topology · Mathematics 2020-09-08 Kyriakos Keremedis , Cenap Özel , Artur Piękosz , Mohammed Al Shumrani , Eliza Wajch

For a metrizable space $X$ of density $\kappa$, let $PM(X)$ be the space of continuous bounded pseudometrics on $X$ endowed with the uniform convergence topology. In this paper, its topology shall be classified as follows: (i) If $X$ is…

General Topology · Mathematics 2022-05-25 Katsuhisa Koshino

Classes of Banach spaces that are finitely, strongly finitely or elementary equivalent are introduced. On sets of these classes topologies are defined in such a way that sets of defined classes become compact totally disconnected…

Functional Analysis · Mathematics 2007-05-23 Eugene Tokarev

We investigate conditions under which a co-computably enumerable closed set in a computable metric space is computable and prove that in each locally computable computable metric space each co-computably enumerable compact manifold with…

Logic in Computer Science · Computer Science 2015-07-01 Zvonko Iljazovic

In this note we prove certain necessary and sufficient conditions for the existence of an embedding of statistical manifolds. In particular, we prove that any compact smooth ($C^1$ resp.) statistical manifold can be embedded into the space…

Differential Geometry · Mathematics 2016-03-11 Hong-Van Le

Suppose G is a topological group containing a (closed) topological copy of the Frechet-Urysohn fan. If G is a perfectly normal sequential space (a normal k-space) then every closed metrizable subset in $G$ is locally compact. Applying this…

General Topology · Mathematics 2011-08-23 Taras Banakh

In these notes we give a brief introduction to decomposition theory and we summarize some classical and well-known results. The main question is that if a partitioning of a topological space (in other words a decomposition) is given, then…

Geometric Topology · Mathematics 2021-03-05 Boldizsar Kalmar

We show that if there exists a topologically expansive homeomorphism on a uniform space, then the space is always a regular space. Through examples we show that in general composition of topologically expansive homeomorphisms need not be…

Dynamical Systems · Mathematics 2019-03-26 Ali Barzanouni , Ekta Shah

An S-approximation space is a novel approach to study systems with uncertainty that are not expressible in terms of inclusion relations. In this work, we further examined these spaces, mostly from a topological point of view by a…

Algebraic Topology · Mathematics 2016-02-03 M. R. Hooshmandasl , M. Alambardar Meybodi , A. K. Goharshady , A. Shakiba

We embed a countably categorical group G into a locally compact group c(G) with a non-trivial topology and study how topological properties of c(G) are connected with the structure of definable subgroups of G.

Logic · Mathematics 2008-11-04 Al. A. Ivanov

A metric space is indivisible if for any partition of it into finitely many pieces one piece contains an isometric copy of the whole space. Continuing our investigation of indivisible metric spaces, we show that a countable ultrametric…

Metric Geometry · Mathematics 2007-05-23 Christian Delhommé , Claude Laflamme , Maurice Pouzet , Norbert Sauer

This article examines Hilbert spaces constructed from sets whose existence is incompatible with the Countable Axiom of Choice (CC). Our point of view is twofold: (1) We examine what can and cannot be said about Hilbert spaces and operators…

Logic · Mathematics 2023-10-27 Bruce Blackadar , Ilijas Farah , Asaf Karagila

The primary objective of this work is to construct spaces that are "pseudocompact but not countably compact," abbreviated as PNC, while endowing them with additional properties. First, motivated by an old problem of van Douwen, we construct…

General Topology · Mathematics 2024-12-03 István Juhász , Ljos Soukup , Zoltán Szentmiklóssy

We study the topology of metric spaces which are definable in o-minimal expansions of ordered fields. We show that a definable metric space either contains an infinite definable discrete set or is definably homeomorphic to a definable set…

Logic · Mathematics 2015-11-12 Erik Walsberg

We construct a family F of compact and pathwise connected subsets of the Euclidean plane such that (i) the cardinality of F is that of the continuum (and hence extremely large) and (ii) if X,Y are distinct spaces in F then there never…

General Topology · Mathematics 2024-01-29 Gerald Kuba

When one considers the collection $\mathcal{H}(\mathbb{R}^n)$ of all compact subsets of $\mathbb{R}^n$ and equip it with a topology, many questions can be asked about the topological space one ends up with. This is an example of a…

General Topology · Mathematics 2022-01-19 Bryant Rosado Silva , Rodney Josué Biezuner

It is an open question (Pawlikowski) whether every finitely generated group can be realized as a fundamental group of a compact metric space. In this paper we prove that any countable group can be realized as the fundamental group of a…

Geometric Topology · Mathematics 2016-02-24 Ziga Virk

A space X is called an alpha-Toronto space if X is scattered of Cantor-Bendixson rank alpha and is homeomorphic to each of its subspaces of same rank. We answer a question of Steprans by constructing a countable alpha-Toronto space for each…

General Topology · Mathematics 2007-05-23 Gary Gruenhage , J. Tatch Moore

We discuss conditions under which certain compactifications of topological spaces can be obtained by composing the ultrafilter space monad with suitable reflectors. In particular, we show that these compactifications inherit their…

General Topology · Mathematics 2024-07-17 Ando Razafindrakoto