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2018 | Buch

Fixed Point Theory in Metric Spaces

Recent Advances and Applications

verfasst von: Prof. Praveen Agarwal, Prof. Mohamed Jleli, Prof. Bessem Samet

Verlag: Springer Singapore

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Über dieses Buch

This book provides a detailed study of recent results in metric fixed point theory and presents several applications in nonlinear analysis, including matrix equations, integral equations and polynomial approximations. Each chapter is accompanied by basic definitions, mathematical preliminaries and proof of the main results. Divided into ten chapters, it discusses topics such as the Banach contraction principle and its converse; Ran-Reurings fixed point theorem with applications; the existence of fixed points for the class of α-ψ contractive mappings with applications to quadratic integral equations; recent results on fixed point theory for cyclic mappings with applications to the study of functional equations; the generalization of the Banach fixed point theorem on Branciari metric spaces; the existence of fixed points for a certain class of mappings satisfying an implicit contraction; fixed point results for a class of mappings satisfying a certain contraction involving extended simulation functions; the solvability of a coupled fixed point problem under a finite number of equality constraints; the concept of generalized metric spaces, for which the authors extend some well-known fixed point results; and a new fixed point theorem that helps in establishing a Kelisky–Rivlin type result for q-Bernstein polynomials and modified q-Bernstein polynomials.
The book is a valuable resource for a wide audience, including graduate students and researchers.

Inhaltsverzeichnis

Frontmatter
Chapter 1. Banach Contraction Principle and Applications
Abstract
Banach contraction principle is a fundamental result in Metric Fixed Point Theory. It is a very popular and powerful tool in solving the existence problems in pure and applied sciences. In this chapter, Banach contraction principle and its converse are presented. Moreover, various applications of this famous principle, including mixed Volterra–Fredholm-type integral equations and systems of nonlinear matrix equations, are provided. Some results of this chapter appeared in [3, 5, 13, 19].
Praveen Agarwal, Mohamed Jleli, Bessem Samet
Chapter 2. On Ran–Reurings Fixed Point Theorem
Abstract
In order to study the existence of solutions to a certain class of nonlinear matrix equations, Ran and Reurings [38] established an extension of Banach contraction principle to metric spaces equipped with a partial order. In this chapter, we present another proof of Ran–Reurings fixed point theorem using Banach contraction principle. Next, we present some applications of this result to the solvability of some classes of matrix equations.
Praveen Agarwal, Mohamed Jleli, Bessem Samet
Chapter 3. The Class of -Contractions and Related Fixed Point Theorems
Abstract
The class of \((\alpha ,\psi )\)-contractions was introduced by Samet et al. [26]. In this chapter, we prove three fixed point theorems for this class of mappings. The presented results are extensions of those obtained in [26]. Moreover, we show that the class of \((\alpha ,\psi )\)-contractions includes as special cases several types of contraction-type mappings, whose fixed points can be obtained by means of Picard iteration. As an application, the existence and uniqueness of solutions to a certain class of quadratic integral equations is discussed. The main references of this chapter are the papers [24, 26].
Praveen Agarwal, Mohamed Jleli, Bessem Samet
Chapter 4. Cyclic Contractions: An Improvement Result
Abstract
In this chapter, we give an improvement fixed point result for cyclic contractions by weakening the closure assumption that is usually supposed in the literature. As applications, we discuss the existence of solutions to certain systems of functional equations. The main reference of this chapter is the paper [4].
Praveen Agarwal, Mohamed Jleli, Bessem Samet
Chapter 5. The Class of JS-Contractions in Branciari Metric Spaces
Abstract
Banach contraction principle has been generalized in many ways over the years. In some generalizations, the contraction is weakened; see [3, 6, 12, 16, 20, 21, 24, 30] and others. In other generalizations, the topology is weakened; see [1, 4, 5, 8, 9, 11, 13, 14, 22, 23, 2729] and others. In [18], Nadler extended Banach fixed point theorem from single-valued maps to set-valued maps. Other fixed point results for set-valued maps can be found in [2, 7, 15, 17, 19] and references therein. In 2000, Branciari [4] introduced the concept of generalized metric spaces, where the triangle inequality is replaced by the inequality \(d(x,y)\le d(x,u)+d(u,v)+d(v,y)\) for all pairwise distinct points \(x,y,u,v\in X\). Various fixed point results were established on such spaces; see, e.g., [1, 8, 13, 14, 22, 23, 28] and references therein. In this chapter, we present a recent generalization of Banach contraction principle on the setting of Branciari metric spaces, which is due to Jleli and Samet [10].
Praveen Agarwal, Mohamed Jleli, Bessem Samet
Chapter 6. Implicit Contractions on a Set Equipped with Two Metrics
Abstract
Several classical fixed point theorems have been unified by considering general contractions expressed via an implicit inequality, see, for examples, Turinici [15], Popa [8, 9], Berinde [2], and references therein. In this chapter, we consider a class of mappings defined on a set equipped with two metrics and satisfying an implicit contraction involving two functions \(F:[0,\infty )^6\rightarrow \mathbb {R}\) and \(\alpha : X\times X\rightarrow \mathbb {R}\). The existence of fixed points for this class of mappings is investigated. The main reference for this chapter is the paper [14].
Praveen Agarwal, Mohamed Jleli, Bessem Samet
Chapter 7. On Fixed Points That Belong to the Zero Set of a Certain Function
Abstract
Let \(T: X\rightarrow X\) be a given mapping. The set \({\text {Fix}}(T)\) is said to be \(\varphi \)-admissible with respect to a certain mapping \(\varphi : X\rightarrow [0,\infty )\), if \(\emptyset \ne \text{ Fix }(T)\subseteq Z_\varphi \), where \(Z_\varphi \) denotes the zero set of \(\varphi \), i.e., \(Z_\varphi =\{x\in X: \varphi (x)=0\}\). In this chapter, we present the class of extended simulation functions recently introduced by Roldán and Samet [13], which is more large than the class of simulation functions, introduced by Khojasteh et al. [8]. We obtain a \(\varphi \)-admissibility result involving extended simulation functions, for a new class of mappings \(T: X\rightarrow X\), with respect to a lower semi-continuous function \(\varphi : X\rightarrow [0,\infty )\), where X is a set equipped with a certain metric d. From the obtained results, some fixed point theorems in partial metric spaces are derived, including Matthews fixed point theorem [9]. Moreover, we answer to three open problems posed by Ioan A. Rus in [16].The main references for this chapter are the papers [7, 13, 17].
Praveen Agarwal, Mohamed Jleli, Bessem Samet
Chapter 8. A Coupled Fixed Point Problem Under a Finite Number of Equality Constraints
Abstract
Let \((E,\Vert \cdot \Vert )\) be a Banach space with a cone P. Let \(F,\varphi _i: E\times E\rightarrow E\) (\(i=1,2,\ldots ,r\)) be a finite number of mappings. In this chapter, we provide sufficient conditions for the existence and uniqueness of solutions to the problem: Find \((x,y)\in E\times E\) such that
$$\begin{aligned} \left\{ \begin{array}{lll} F(x,y)&{}=&{}x,\\ F(y,x)&{}=&{}y,\\ \varphi _i(x,y)&{}=&{}0_E,\,\, i=1,2,\ldots ,r, \end{array} \right. \end{aligned}$$
where \(0_E\) is the zero vector of E. The main reference for this chapter is the paper [4].
Praveen Agarwal, Mohamed Jleli, Bessem Samet
Chapter 9. JS-Metric Spaces and Fixed Point Results
Abstract
In this chapter, we present a recent concept of generalized metric spaces due to Jleli and Samet [12], for which we extend some well-known fixed point results including Banach contraction principle, Ćirić’s fixed point theorem, a fixed point result due to Ran and Reurings, and a fixed point result due to Nieto and Rodriguez-Lopez. This new concept of generalized metric spaces recovers various topological spaces including standard metric spaces, b-metric spaces, dislocated metric spaces, and modular spaces.
Praveen Agarwal, Mohamed Jleli, Bessem Samet
Chapter 10. Iterated Bernstein Polynomial Approximations
Abstract
Kelisky and Rivlin [7] proved that each Bernstein operator \(B_n\) is a weaky Picard operator (WPO). Moreover, given \(n\in \mathbb {N}\) and \(\varphi \in C([0,1];\mathbb {R})\),
$$ \lim _{j\rightarrow \infty }(B_n^j\varphi )(t) = \varphi (0) + (\varphi (1)- \varphi (0))t, \quad t \in [0, 1]. $$
Praveen Agarwal, Mohamed Jleli, Bessem Samet
Backmatter
Metadaten
Titel
Fixed Point Theory in Metric Spaces
verfasst von
Prof. Praveen Agarwal
Prof. Mohamed Jleli
Prof. Bessem Samet
Copyright-Jahr
2018
Verlag
Springer Singapore
Electronic ISBN
978-981-13-2913-5
Print ISBN
978-981-13-2912-8
DOI
https://doi.org/10.1007/978-981-13-2913-5