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Related papers: Extremally $T_1$-spaces and Related Spaces

200 papers

In this article, we analyse the structure of finite dimensional subspaces of the set of points of strong subdifferentiability in a dual space. In a dual $L_1(\mu)$ space, such a subspace is in the discrete part of the Yoshida-Hewitt type…

Functional Analysis · Mathematics 2020-10-27 C. R. Jayanarayanan , T. S. S. R. K. Rao

The question of the existence of Universal homotopy commutative and homotopy associative H-spaces (called Abelian H-spaces) is studied. Such a space T(X) would prolong a map from X into an Abelian H-space to a unique H-map from T into X.…

Algebraic Topology · Mathematics 2011-02-07 Brayton Gray

A datatset $X$ on $R^2$ is a finite topological space. Current research of a dataset focuses on statistical methods and the algebraic topological method \cite{carlsson}. In \cite{hu}, the concept of typed topological space was introduced…

Machine Learning · Computer Science 2025-08-20 Wanjun Hu

We study Michael's lower semifinite topology and Fell's topology on the collection of all closed limit subsets of a topological space. Special attention is given to the subfamily of all maximal limit sets.

General Topology · Mathematics 2008-11-21 Aldo J. Lazar

This paper introduces a novel class of topological spaces, termed SC*-regular spaces, which are defined using SC*-open sets. We explore their fundamental properties and examine their connections with existing regularity concepts, such as…

General Topology · Mathematics 2025-05-16 Neeraj Kumar Tomar , Amit Ujlayan , M. C. Sharma

The kernel of analysis, to me anyway, is the following idea: A point is arbitrarily close to a set if every neighborhood of the point intersects the set. Defining ``arbitrarily close'' in this way provides a foundation for classical results…

History and Overview · Mathematics 2022-08-22 John A. Rock

The C*-envelope of the limit algebra (or limit space) of a contractive regular system of digraph algebras (or digraph spaces) is shown to be an approximately finite C*-algebra and the direct system for the C*-envelope is determined…

funct-an · Mathematics 2008-02-03 C. Laurie , S. C. Power

A ringed finite space is a ringed space whose underlying topological space is finite. The category of ringed finite spaces contains, fully faithfully, the category of finite topological spaces and the category of affine schemes. Any ringed…

Algebraic Geometry · Mathematics 2015-11-20 Fernando Sancho de Salas

The purpose of this paper is to introduce a Zariski-like topology on the spectrum of all proper ideals of a ring. We show that the space is T_0, quasi-compact, and every irreducible closed subset has a unique generic point. Furthermore,…

Commutative Algebra · Mathematics 2022-03-22 Amartya Goswami

We give several characteristic properties of FAC spaces, namely topological spaces with no infinite discrete subspace. The first one was obtained in 2019 by the first author, and states that every closed set is a finite union of irreducible…

General Topology · Mathematics 2023-09-25 Jean Goubault-Larrecq , Maurice Pouzet

In this paper we continue the analysis undertaken in a series of previous papers on structures arising as completions of C*-algebras under topologies coarser that their norm and we focus our attention on the so-called {\em locally convex…

Mathematical Physics · Physics 2015-10-27 Camillo Trapani , Salvatore Triolo

A topological space $X$ is called hereditarily supercompact if each closed subspace of X is supercompact. By a combined result of Bula, Nikiel, Tuncali, Tymchatyn, and Rudin, each monotonically normal compact Hausdorff space is hereditarily…

General Topology · Mathematics 2014-12-04 Taras Banakh , Zdzislaw Kosztolowicz , Slawomir Turek

We investigate $\mathcal F$-Borel topological spaces. We focus on finding out how a~complexity of a~space depends on where the~space is embedded. Of a~particular interest is the~problem of determining whether a~complexity of given space $X$…

General Topology · Mathematics 2020-02-24 Vojtěch Kovařík

We introduce a new covering property, defined in terms of order types of sequences of open sets, rather than in terms of cardinalities of families. The most general form of this compactness notion depends on two ordinal parameters. In the…

General Topology · Mathematics 2021-02-09 Paolo Lipparini

Recently a new kind of approximation to continuum topological spaces has been introduced, the approximating spaces being partially ordered sets (posets) with a finite or at most a countable number of points. The partial order endows a poset…

q-alg · Mathematics 2008-02-03 Elisa Ercolessi , Giovanni Landi , Paulo Teotonio-Sobrinho

We revisit the known problem whether each compact topology is contained in a maximal compact topology and collect some partial answers to this question. For instance we show that each compact topology is contained in a compact topology in…

General Topology · Mathematics 2007-05-23 Hans-Peter A. Künzi , Dominic van der Zypen

Generalized topological spaces in the sense of Cs\'{a}sz\'{a}r have two main features which distinguish them from typical topologies. First, these families of subsets are not closed under intersections. Second, we allow for the possibility…

Logic · Mathematics 2019-09-23 Tomasz Witczak

We propose a homology theory for locally compact spaces with ends in which the ends play a special role. The approach is motivated by results for graphs with ends, where it has been highly successful. But it was unclear how the original…

Algebraic Topology · Mathematics 2011-05-26 Reinhard Diestel , Philipp Sprüssel

The fundamental aim of this paper is to introduce and investigate a new property of quasi 2-normed space based on a question given by C. Park (2006) [2] for the completion quasi 2-normed space. Finally, we also find an answer for a question…

Combinatorics · Mathematics 2019-07-04 Mehmet Kir , Mehmet Acikgoz

Affinely closed homogeneous spaces G/H, i.e., affine homogeneous spaces that admit only the trivial affine embedding, are characterized for any affine algebraic group G. As a corollary, a description of affine G-algebras with finitely…

Algebraic Geometry · Mathematics 2009-08-22 Ivan V. Arzhantsev , Natalia A. Tennova