Methods of Functional Analysis
and Topology
Editors-in-Chief: A. N. Kochubei,
G. M. Torbin
ISSN: 1029-3531 (Print), 2415-7503 (Online)
Founded by Yu. M. Berezansky in 1995.
Methods of Functional Analysis and Topology (MFAT), founded in 1995, is a peer-reviewed journal publishing original articles and surveys on general methods and techniques of functional analysis and topology with a special emphasis on applications to modern mathematical physics.
MFAT is an open access journal, free for authors and free for readers.
Indexed in: MathSciNet, zbMATH, Scopus, Web of Science, DOAJ, Google Scholar
Latest Articles (September, 2025)
Inertial KM-type algorithm for solving split monotone variational inclusion problem and hierarchical fixed point problem
Mubashshir U. Khairoowala, Shamshad Husain, Mohd Furkan
MFAT 31 (2025), no. 3, 222-237
222-237
The primary objective of this paper is to present and investigate an inertial Krasnoselski-Mann (KM) type iterative method for approximating a common solution to a split monotone variational inclusion problem and a hierarchical fixed point problem for a finite family of $l$-strictly pseudocontractive non-self mappings. Additionally, we demonstrate that the iterative sequences provided by the proposed method converge weakly to a common solution to these problems. The methodology and conclusions described in this work extend and unify previously published findings in this domain. Finally, a numerical example is presented to demonstrate the suggested iterative method's convergence analysis of the sequences obtained. We also carried out a justification how the inertial term is useful.
Fixed Point Theorem for $\psi$-Geraghty Contraction Type Mappings in b-Metric Spaces with Application
Sabita Kumari, Sandip Shrivastava, Shraddha Rajput
MFAT 31 (2025), no. 3, 238-246
238-246
In this paper, we introduce a new class of contractive mappings, called generalized $\psi$-Geraghty contractions, in the framework of b-complete metric spaces. We establish a unique fixed-point theorem that extends existing results in fixed-point theory. An illustrative example with a graphical representation demonstrates the validity of our findings. Furthermore, we apply the main result to an integral equation, highlighting its effectiveness in ensuring the existence and uniqueness of solutions. This work underscores the theoretical significance and practical applicability of generalized $\psi$-Geraghty contractions in mathematics, physics, and engineering.
On $m$-quasi-$n$-power-totally-$(\alpha,\beta)$-normal operators
Pradeep Radhakrishnan, Sid Ahmed Ould Ahmed Mahmoud, P. Maheswari Naik
MFAT 31 (2025), no. 3, 247-260
247-260
In this paper, we introduce the notion of $m$-quasi-$n$-power-totally-$(\alpha,\beta)$-normal operators on a Hilbert space $\mathscr{H}$ as : An operator $\mathcal{L}$ is called $m$-quasi-$n$-power-totally-$(\alpha,\beta)$-normal $(0\leq \alpha \leq 1 \leq \beta)$ if \begin{align*} \alpha^{2}\mathcal{L}^{m*}(\mathcal{L}-\lambda)^{*}(\mathcal{L}-\lambda )^{n}\mathcal{L}^{m}& \leq \mathcal{L}^{m*}(\mathcal{L}-\lambda)^{n}(\mathcal{L}-\lambda)^{*}\mathcal{L}^{m}\\ &\leq \beta^{2} \mathcal{L}^{m*}(\mathcal{L}-\lambda)^{*}(\mathcal{L}-\lambda )^{n}\mathcal{L}^{m} \end{align*} for natural numbers $m$ and $n$ and for all $\lambda \in \mathbb{C}$. This paper aims to study several properties of $m$-quasi-$n$-power-totally-$(\alpha,\beta)$-normal operators.
Bisingular Integral with Summable Density
↓ Abstract
MFAT 31 (2025), no. 3, 153-160
153-160
In this paper, we introduce new metric characteristics in the space of summable functions. Using these metric characteristics it is obtained Zigmund-type inequalities for the bisingular integral. It is constructed an invariant $T_p$ space for bisingular integral operator according to the inequality. Furthermore, the existence and uniqueness of the solution to the nonlinear bisingular integral equation within the invariant space $T_p$ are proven using the method of successive approximations.