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Some results on fixed points related to the contractive compositions of bounded operators in complete metric spaces are discussed through the manuscript. The class of composite operators under study can include, in particular, sequences of…

Functional Analysis · Mathematics 2012-08-30 M. De la Sen

We show that (for the weak operator topology) the set of unitary operators on a separable infinite-dimensional Hilbert space is residual in the set of all contractions. The analogous result holds for isometries and the strong operator…

Functional Analysis · Mathematics 2014-12-02 Tanja Eisner

In this paper, we study the existence of fixed points for mappings defined on complete (compact) metric space (X, d) satisfying a general contractive (contraction) inequality depended on another function. These conditions are analogous to…

Functional Analysis · Mathematics 2009-03-10 A. Beiranvand , S. Moradi , M. Omid , H. Pazandeh

For a topological space $X$ a topological contraction on $X$ is a closed mapping $f:X\to X$ such that for every open cover of $X$ there is a positive integer $n$ such that the image of the space $X$ via the $n$th iteration of $f$ is a…

General Topology · Mathematics 2026-02-04 Michał Morayne , Robert Rałowski

In this article we discuss the solvability of some class of fully nonlinear equations, and equations with p-Laplacian in more general conditions by using a new approach given in [1] for studying the nonlinear continuous operator. Moreover…

Analysis of PDEs · Mathematics 2012-08-14 Kamal N. Soltanov

In this paper, we study the existence of the random fixed points under mild continuity assumptions. The main theorems consider the almost lower semicontinuous operators defined on Frechet spaces and also operators having properties weaker…

Probability · Mathematics 2013-12-02 Monica Patriche

We establish fixed point theorems for nonlinear contractions on a metric space (not essentially complete) endowed with an arbitrary binary relation. Our results extend, generalize, modify and unify several known results especially those…

General Topology · Mathematics 2016-11-15 Md Ahmadullah , Mohammad Imdad , Rqeeb Gubran

In this paper, we introduce the notion of $\alpha$--contractive mapping of Meir--Keeler type in complete metric spaces and prove new theorems which assure the existence, uniqueness and iterative approximation of the fixed point for this…

General Topology · Mathematics 2013-03-26 Maher Berzig , Mircea-Dan Rus

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

There are presented certain results on extending continuous linear operators defined on spaces of E-valued continuous functions (defined on a compact Hausdorff space X) to linear operators defined on spaces of E-valued measurable functions…

Functional Analysis · Mathematics 2017-05-26 Piotr Niemiec

A new technique for proving fixed point theorems for families of holomorphic transformations of operator balls is developed. One of these theorems is used to show that a bounded representation in a real or complex Hilbert space is…

Metric Geometry · Mathematics 2011-09-02 M. I. Ostrovskii , V. S. Shulman , L. Turowska

Startpoints (resp. endpoints) can be defined as "oriented fixed points". They arise naturally in the study of fixed for multi-valued maps defined on quasi-metric spaces. In this article, we give a new result in the startpoint theory for…

General Topology · Mathematics 2018-04-02 Collins Amburo Agyingi , Yaé Ulrich Gaba

The class of O-metric spaces generalize several existing metric-types in literature including metric spaces, b-metric spaces, and ultra metric spaces. In this paper, we discuss the properties of the topology induced by an O-metric and…

General Mathematics · Mathematics 2025-04-29 Hallowed O. Olaoluwa , Aminat O. Ige , Johnson O. Olaleru

In this article we extend the notion of orthogonal metric space to weak orthogonal metric space. Then we establish fixed point results for a mapping satisfying a more general contraction condition. Several nontrivial examples are given in…

Functional Analysis · Mathematics 2018-06-27 Tanusri Senapati

Given an action by a finite quantum group $\mathbb{G}$ on a von Neumann algebra $M$, we prove that a number of familiar $W^*$ properties are equivalent for $M$ and the fixed-point algebra $M^{\mathbb{G}}$ (i.e. hold or not simultaneously…

Operator Algebras · Mathematics 2025-04-22 Alexandru Chirvasitu

In this oaper, we prove some fixed point theorems in metric vector spaces, in which the continuity is not required for the considered mappings to satisfy. We provide some concrete examples to demonstrate these theorems. We also give some…

Functional Analysis · Mathematics 2022-11-08 Jinlu Li

We describe fixed points of an infinite dimensional non-linear operator related to a hard core (HC) model with a countable set $\mathbb{N}$ of spin values on the Cayley tree. This operator is defined by a countable set of parameters…

Mathematical Physics · Physics 2023-03-22 U. R. Olimov , U. A. Rozikov

Using the setting of $G$-metric spaces, common fixed point theorems for four maps satisfying the weakly commuting conditions are obtained for various generalized contractive conditions. Several examples are also presented to show the…

General Topology · Mathematics 2023-07-24 Talat Nazir , Sergei Silvestrov

In this paper, we establish coincidence fixed point and common fixed point theorems for two mapping in complete $C^*$-algebra-valued metric spaces which satisfy new contractive conditions. Some applications of our obtained results are…

Functional Analysis · Mathematics 2015-07-01 Xin Qiaoling , Jiang Lining , Ma Zhenhua

The \emph{Continuity Problem} is the question whether effective operators are continuous, where an effective operator $F$ is a function on a space of constructively given objects $x$, defined by mapping construction instructions for $x$ to…

Logic · Mathematics 2021-11-15 Dieter Spreen