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Related papers: Borsuk-Ulam type theorems for metric spaces

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In this paper, we introduce an extension of rectangular metric spaces called controlled rectangular metric spaces, by changing the rectangular inequality as follows: \begin{equation*} d(x, y)\leq\alpha(x, u)d(x, u)+\alpha(u, v)d(u,…

General Topology · Mathematics 2022-01-19 Mohamed Rossafi , Abdelkarim Kari

Let $X$ be metrizable, $Y$ be perfectly normal and suppose that there exists a uniformly continuous surjection $T: C_{p}(X) \to C_{p}(Y)$ (resp., $T: C_{p}^*(X) \to C_{p}^*(Y)$), where $C_{p}(X)$ (resp., $C_{p}^*(X)$) denotes the space of…

General Topology · Mathematics 2025-05-06 A. Eysen , A. Leiderman , V. Valov

We study the problem of topologically order-embedding a given topological poset X in the space of all closed subsets of X which is topologized by the Fell topology and ordered by set inclusion. We show that this can be achieved whenever X…

General Topology · Mathematics 2021-11-24 Gerald Beer , Efe A. Ok

Let $X$ and $Y$ be topological spaces, let $Z$ be a metric space, and let $f: X\times Y\to Z$ be a mapping. It is shown that when $Y$ has a countable base $\mathcal B$, then under a rather general condition on the set-valued mappings $X\ni…

General Topology · Mathematics 2010-10-04 Ahmed Bouziad , Jean-Pierre Troallic

In this paper, we examine linear conditions on finite sets of points in projective space implied by the Cayley-Bacharach condition. In particular, by bounding the number of points satisfying the Cayley-Bacharach condition, we force them to…

Algebraic Geometry · Mathematics 2022-01-07 Jake Levinson , Brooke Ullery

In this present article, we get sufficient conditions for the existence and uniqueness of fixed points and common fixed points for single and double mapping satisfying various contractive conditions within the partially ordered…

General Mathematics · Mathematics 2017-05-29 Meltem Kaya , Hasan Furkan

A self-map $T$ of a $\nu$-generalized metric space $(X,d\,)$ is said to be a Ciric-Matkowski contraction if $d(Tx,Ty)<d(x,y)$, for $x\neq y$, and, for every $\epsilon>0$, there is $\delta>0$ such that $d(x,y)<\delta+\epsilon$ implies…

General Topology · Mathematics 2015-06-01 Mortaza Abtahi

In this work, a metric is presented on the set of boundedly-compact pointed metric spaces that generates the Gromov-Hausdorff topology. A similar metric is defined for measured metric spaces that generates the Gromov-Hausdorff-Prokhorov…

Metric Geometry · Mathematics 2020-01-10 Ali Khezeli

Let $(A, B)$ be a nonempty bounded closed convex proximal parallel pair in a nearly uniformly convex Banach space and $T: A\cup B \rightarrow A\cup B$ be a continuous and asymptotically relatively nonexpansive map. We prove that there…

Functional Analysis · Mathematics 2016-11-09 S. Rajesh , P. Veeramani

In the present paper, we study the existence of best proximity pair in ultrametric spaces. We show, under suitable assumptions, that the proximinal pair $(A,B)$ has a best proximity pair. As a consequence we generalize a well known best…

Functional Analysis · Mathematics 2021-04-15 Karim Chaira , Samih Lazaiz

We show that the continuum hypothesis implies there exists a Lindelof space X such that X x X is the union of two metrizable subspaces but X is not metrizable. This gives a consistent solution to a problem of Balogh, Gruenhage, and Tkachuk.…

Logic · Mathematics 2007-05-23 Arnold W. Miller

We give a simple and physically intuitive necessary and sufficient condition for a map acting on a compact metric space to be mixing (i.e. infinitely many applications of the map transfer any input into a fixed convergency point). This is a…

Quantum Physics · Physics 2007-06-13 Daniel Burgarth , Vittorio Giovannetti

We show that the space of continuous functions over a compact space X admits an equivalent pointwise-lowersemicontinuous locally uniformly rotund norm whenever X admits a fully closed map onto a compact Y such that C(Y) and the spaces of…

Functional Analysis · Mathematics 2023-12-27 Todor Manev

In this note, we discuss some fixed point theorems for contractive self mappings defined on a $G$-metric spaces. More precisely, we give fised point theorems for mappings with a contractive iterate at a point.

General Topology · Mathematics 2017-02-24 Yaé Olatoundji Gaba

We give a characterization of completely regular topological spaces. Applying some recent results for supinf problems in completely regular topological spaces we establish a variational principle for saddle points. Well-posedness of saddle…

Optimization and Control · Mathematics 2024-08-05 D. Kamburova , R. Marinov , N. Zlateva

In a spherically complete ultrametric space, a strictly contracting mapping has a fixed point. We indicate in this paper how this fixed point can either be reached or approximated.

Metric Geometry · Mathematics 2013-07-25 Sibylla Priess-Crampe , Paulo Ribenboim

The embedding theorem arises in several problems from analysis and geometry. The purpose of this paper is to provide a deeper understanding of analysis and geometry with a particular focus on embedding theorems on spaces of homogeneous type…

Classical Analysis and ODEs · Mathematics 2016-01-25 Yanchang Han , Yongsheng Han , Ji Li

We study topological groups of monotonic autohomeomorphisms on a generalized ordered space $L$. We find a condition that is necessary and sufficient for the set of all monotonic autohomeomorphisms on $L$ along with the function composition…

General Topology · Mathematics 2022-12-20 Raushan Buzyakova

We give an intuitive combinatorial proof of Ky Fan's covering lemma based on the Borsuk-Ulam theorem. We then show how this approach can be generalized to Ky Fan's covering lemma for several linear orders.

Combinatorics · Mathematics 2025-07-31 Bogdan Chornomaz

In this paper we prove FG-coupled fixed point theorems for different contractive mappings and generalized quasi- contractive mappings in partially ordered complete metric spaces. We prove the existence of FG-coupled fixed points of…

General Topology · Mathematics 2016-04-12 Deepa Karichery , Shaini Pulickakunnel
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