English
Related papers

Related papers: Uniform covers at non-isolated points

200 papers

In a countably normed space which is a linear space equipped with a countable number of pair-wise compatible norms, we prove the existence of a common nearest point (in all norms) from a point outside a nonempty subset if this subset is…

Functional Analysis · Mathematics 2022-12-14 Moustafa M. Zakaria , Nashat Faried , Hany A. El-Sharkawy

In this paper, we discuss the existence of fixed points for integral type contractions in uniform spaces endowed with both a graph and an $E$-distance. We also give two sufficient conditions under which the fixed point is unique. Our main…

General Topology · Mathematics 2013-06-03 Aris Aghanians , Kourosh Nourouzi

We construct a Banach space satisfying that the nearest point map (also called proximity mapping or metric projection) onto any compact and convex subset is continuous but not uniformly continuous. The space we construct is locally…

Functional Analysis · Mathematics 2024-02-08 Rubén Medina , Andrés Quilis

The first aim of this study is to define soft sequential compact metric spaces and to investigate some important theorems on soft sequential compact metric space. Second is to introduce net and totally bounded soft metric space and study…

General Mathematics · Mathematics 2013-08-16 Sadi Bayramov , Cigdem Gunduz , Murat I. Yazar

The main aim of the paper is to give a full classification (up to isometry) of all metric spaces X with the following two properties: X contains a compact set with non-empty interior; and for any three distinct points a, b and c of X there…

Metric Geometry · Mathematics 2025-01-08 Piotr Niemiec

In this paper we introduce an interlacing condition on the elements of a family of operators that allows us to gather together a number of results on fixed points and common fixed points for single and families of mappings defined on metric…

Functional Analysis · Mathematics 2022-12-29 Rafael Espínola , Maria Japón , Daniel Souza

This paper presents a new version of boundary on coarse spaces. The space of ends functor maps coarse metric spaces to uniform topological spaces and coarse maps to uniformly continuous maps.

Metric Geometry · Mathematics 2019-07-08 Elisa Hartmann

In this article we studied the relationship between metric spaces and multiplicative metric spaces. Also, we pointed out some fixed and common fixed point results under some contractive conditions in multiplicative metric spaces can be…

General Topology · Mathematics 2015-12-14 K. Abodayeh , A. Pitea , W. Shatanawi , T. Abdeljawad

Given a partially ordered set $P$ we study properties of topological spaces $X$ admitting a $P$-base, i.e., an indexed family $(U_\alpha)_{\alpha\in P}$ of subsets of $X\times X$ such that $U_\beta\subset U_\alpha$ for all $\alpha\le\beta$…

General Topology · Mathematics 2021-11-01 Taras Banakh

In this paper the theory of uniformly convex metric spaces is developed. These spaces exhibit a generalized convexity of the metric from a fixed point. Using a (nearly) uniform convexity property a simple proof of reflexivity is presented…

Metric Geometry · Mathematics 2016-04-08 Martin Kell

We investigate several boundedness properties of function spaces considered as uniform spaces.

General Topology · Mathematics 2018-02-19 Lubica Hola , Ljubisa D. R. Kocinac

The aim of this paper is to investigate the equivalence conditions for uniform perfectness of quasi-metric spaces. We also obtain the invariant property of uniform perfectness under quasim\"obius maps in quasi-metric spaces. In the end, two…

Complex Variables · Mathematics 2019-03-05 Qingshan Zhou , Yaxiang Li , Ailing Xiao

For a non-compact metrizable space $X$, let ${\mathcal E}(X)$ be the set of all one-point metrizable extensions of $X$, and when $X$ is locally compact, let ${\mathcal E}_K(X)$ denote the set of all locally compact elements of ${\mathcal…

General Topology · Mathematics 2015-06-25 M. R. Koushesh

Some known fixed point theorems for nonexpansive mappings in metric spaces are extended here to the case of primitive uniform spaces. The reasoning presented in the proofs seems to be a natural way to obtain other general results.

General Topology · Mathematics 2021-04-09 Lech Pasicki

We study the isoperimetric problem in product spaces equipped with the uniform distance. Our main result is a characterization of isoperimetric inequalities which, when satisfied on a space, are still valid for the product spaces, up a to a…

Functional Analysis · Mathematics 2014-11-14 Franck Barthe , Benoit Huou

We generalize the concept of mutually unbiased bases (MUB) to measurements which are not necessarily described by rank one projectors. As such, these measurements can be a useful tool to study the long standing problem of the existence of…

Quantum Physics · Physics 2015-06-18 Amir Kalev , Gilad Gour

A topological space $X$ is defined to have a neighborhood $P$-base at any $x\in X$ from some poset $P$ if there exists a neighborhood base $(U_p[x])_{p\in P}$ at $x$ such that $U_p[x]\subseteq U_{p'}[x]$ for all $p\geq p'$ in $P$. We prove…

General Topology · Mathematics 2021-05-21 Ziqn Feng

It is shown that a separated sequence of points in the unit disc of the complex plane is in fact uniformly separated, if there exists a certain intermediate sequence whose separated subsequences are uniformly separated. This property is…

Classical Analysis and ODEs · Mathematics 2018-10-01 Janne Gröhn , Artur Nicolau

In this note we study some properties of topological entropy for noncompact non-metrizable spaces.

Dynamical Systems · Mathematics 2019-12-19 Seyyed Alireza Ahmadi , Xinxing Wu , Guanrong Chen

Author developed a uniform model for different spaces where distance and angle measure kinds are parameters. This model is calculus centric, but can also be used in theoretical research. It is useful in the following domains: deduction of…

Metric Geometry · Mathematics 2018-07-30 Alexandru Popa