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

200 papers

The purpose of this note is to describe a space that is regular but not completely regular, but only barely so: all closed sets are $G_\delta$-sets and every singleton is a zero-set.

General Topology · Mathematics 2025-08-20 Klaas Pieter Hart

Monotone determined spaces are natural topological extensions of dcpo. Its main purpose is to build an extended framework for domain theory. In this paper, we study the one-step closure and ideal convergence on monotone determined space.…

General Topology · Mathematics 2022-12-14 Wu Wang

Let $\{T(t)\}_{t\geq0}$ be a $C_0$-semigroup on an infinite dimensional separable Hilbert space; a suitable definition of near $\{T(t)^*\}_{t\geq0}$ invariance of a subspace is presented in this paper. A series of prototypical examples for…

Functional Analysis · Mathematics 2020-12-22 Yuxia Liang , Jonathan R. Partington

For bi-Lipschitz homeomorphisms of a compact manifold it is known that topological entropy is always finite. For compact manifolds of dimension two or greater, we show that in the closure of the space of bi-Lipschitz homeomorphisms, with…

Dynamical Systems · Mathematics 2017-09-11 Edson de Faria , Peter Hazard , Charles Tresser

Let F<X> be the free unitary associative algebra over a field F on the set X = {x_1, x_2, ...}. A vector subspace V of F<X> is called a T-subspace (or a T-space) if V is closed under all endomorphisms of F<X>. A T-subspace V in F<X> is…

Rings and Algebras · Mathematics 2013-10-30 Dimas José Gonçalves , Alexei Krasilnikov , Irina Sviridova

Given a compact metric space $X$, we associate to it an inverse sequence of finite $T_0$ topological spaces. The inverse limit of this inverse sequence contains a homeomorphic copy of $X$ that is a strong deformation retract. We provide a…

Geometric Topology · Mathematics 2022-03-14 Pedro J. Chocano , Manuel A. Morón , Francisco R. Ruiz del Portal

The aim of this paper is to propose an abstract construction of spaces which keep the main properties of the (already known) Hardy spaces H^1. We construct spaces through an atomic (or molecular) decomposition. We prove some results about…

Functional Analysis · Mathematics 2007-12-20 Frederic Bernicot , Jiman Zhao

We define and study a class of finite topological spaces, which model the cell structure of a space obtained by gluing finitely many Euclidean convex polyhedral cells along congruent faces. We call these finite topological spaces,…

Algebraic Topology · Mathematics 2008-07-28 Tathagata Basak

We study abstract Ces\`aro spaces $CX$, which may be regarded as generalizations of Ces\`aro sequence spaces $ces_p$ and Ces\`aro function spaces $Ces_p(I)$ on $I = [0,1]$ or $I = [0,\infty)$, and also as the description of optimal domain…

Functional Analysis · Mathematics 2014-03-21 Karol Leśnik , Lech Maligranda

We consider a generalization of the interior Schwarzschild solution that we match to the exterior one to build global C^1 models that can have arbitrary large mass, or density, with arbitrary size. This is possible because of a new insight…

General Relativity and Quantum Cosmology · Physics 2015-06-25 J. M. Aguirregabiria , Ll. Bel

Let $\rho_1$ and $\rho_2$ be two states on $\mathbb{C}^{d_1}$ and $\mathbb{C}^{d_2}$ respectively. The marginal state space, denoted by $\mathcal{C}(\rho_1,\rho_2)$, is the set of all states $\rho$ on $\mathbb{C}^{d_1}\otimes…

Operator Algebras · Mathematics 2026-02-20 Repana Devendra , Pankaj Dey , Santanu Dey

We show that there is a compact topological space carrying a measure which is not a weak* limit of finitely supported measures but is in the sequential closure of the set of such measures. We construct compact spaces with measures of…

General Topology · Mathematics 2012-09-21 Piotr Borodulin-Nadzieja , Omar Selim

Our work aims to introduce generalization of soft $ \mu $-compact soft generalized topological spaces, namely; soft nearly $ \mu $-compact spaces which are defined over initial universe with a fixed set of parameters. Basic properties and…

General Topology · Mathematics 2016-10-07 Mariam Abuage , A. Kiliçman , Mohammad S. Sarsak

This survey/expository article covers a variety of topics related to the "topology at infinity" of noncompact manifolds and complexes. In manifold topology and geometric group theory, the most important noncompact spaces are often…

Geometric Topology · Mathematics 2021-03-02 Craig R. Guilbault

In the paper we study relations of rigidity, equicontinuity and pointwise recurrence between a t.d.s. $(X,T)$ and the t.d.s. $(K(X),T_K)$ induced on the hyperspace $K(X)$ of all compact subsets of $X$, and provide some characterizations.…

Dynamical Systems · Mathematics 2015-05-01 Jie Li , Piotr Oprocha , Xiangdong Ye , Ruifeng Zhang

We define E-theory for separable C*-algebras over second countable topological spaces and establish its basic properties. This includes an approximation theorem that relates the E-theory over a general space to the E-theories over finite…

K-Theory and Homology · Mathematics 2015-10-23 Marius Dadarlat , Ralf Meyer

For a separable locally compact but not compact metrizable space $X$, let $\alpha X = X \cup \{x_\infty\}$ be the one-point compactification with the point at infinity $x_\infty$. We denote by $EM(X)$ the space consisting of admissible…

General Topology · Mathematics 2022-02-18 Katsuhisa Koshino

The study of infra-topological spaces focuses on characterizations of $e^\star$-open sets and nearby open sets in infra-topological spaces. The $e^\star$-open sets, a variation of open sets, are explored for their unique properties and…

General Topology · Mathematics 2024-03-05 G. Saravanakumar , D. Jaya Priya

The aim of this paper is to continue the study of sg-compact spaces. The class of sg-compact spaces is a proper subclass of the class of hereditarily compact spaces. In our paper we shall consider sg-compactness in product spaces. Our main…

General Topology · Mathematics 2007-05-23 Julian Dontchev , Maximilian Ganster

For every finite closure space $X$ one can define a finite topological space $\operatorname{Top} X$ together with a natural projection $\operatorname{Top} X\longrightarrow X$. This could allow to apply the techniques of topological…

General Topology · Mathematics 2021-11-29 Josef Eschgfäller