John Michael Rassias
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
John Michael Rassias has a total of 75 co-authors. Here are the top co-authors by number of shared publications:
- Abasalt Bodaghi
Department of Mathematics, WT.C., Islamic Azad University, Tehran, Iran
6 shared publications - Beri Venkatachalapathy Senthil Kumar
Department of Mathematics, C. Abdul Hakeem College of Engineering and Technology, Melvisharam, India
4 shared publications - Choonkil Park
Hanyang University
3 shared publications - Kandhasamy Tamilvanan
Department of Mathematics, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Tandalam, Chennai 602105, Tamil Nadu, India
3 shared publications - Krishnan Ravi
Department of Mathematics Sacred Heart College Tirupattur-635 601 TamilNadu India
3 shared publications - Mohammad Sal Moslehian
Department of Pure Mathematics, Faculty of Mathematical Sciences, Ferdowsi University of Mashhad, Mashhad, Iran
3 shared publications
Latest Publications
- Open Access
- 20 July 2026
- Published by MDPI AG in Mathematics
- Vol. 14 (14) , 2638
Approximate Quadratic ∗-Derivations in ρ-Complete Convex n-Modular ∗-Algebras
In this paper, we introduce the following quadratic functional equation: which is derived from a geometric median identity in the Euclidean plane. Then, we find a general solution to the quadratic functional equation and prove the stability results of the quadratic ∗-derivations in -complete convex n-modular ∗-algebras.- 20 July 2026
- Published by MDPI AG in Mathematics
- Vol. 14 (14) , 2638
Open AccessApproximate Quadratic ∗-Derivations in ρ-Complete Convex n-Modular ∗-Algebras
In this paper, we introduce the following quadratic functional equation: which is derived from a geometric median identity in the Euclidean plane. Then, we find a general solution to the quadratic functional equation and prove the stability results of the quadratic ∗-derivations in -complete convex n-modular ∗-algebras. - Open Access
- 1 January 2025
- Published by Wilmington Scientific Publisher, LLC in Journal of Applied Analysis & Computation
- Vol. 15 (3) , 1770-1785
SOME STUDIES ON EULER-LAGRANGE QUARTIC FUNCTIONAL EQUATIONS IN β-NORMED SPACES
In this paper, we study two types of Euler-Lagrange functional equations that map $ \jmath $ from normed spaces to $ \beta $-normed spaces using quartic functional equations. We will investigate the inequality under various transformations and perturbations using both fixed point and direct methods, to establish the Hyers-Ulam stability of quartic Euler-Lagrange functional equations.- 1 January 2025
- Published by Wilmington Scientific Publisher, LLC in Journal of Applied Analysis & Computation
- Vol. 15 (3) , 1770-1785
Open AccessSOME STUDIES ON EULER-LAGRANGE QUARTIC FUNCTIONAL EQUATIONS IN β-NORMED SPACES
In this paper, we study two types of Euler-Lagrange functional equations that map $ \jmath $ from normed spaces to $ \beta $-normed spaces using quartic functional equations. We will investigate the inequality under various transformations and perturbations using both fixed point and direct methods, to establish the Hyers-Ulam stability of quartic Euler-Lagrange functional equations. - Open Access
On the Generalized Stabilities of Functional Equations via Isometries
The main goal of this research article is to investigate the stability of generalized norm-additive functional equations. This study demonstrates that these equations are Hyers-Ulam stable for surjective functions from an arbitrary group G to a real Banach space B using the large perturbation method. Furthermore, hyperstability results are investigated for a generalized Cauchy equation.
Open AccessOn the Generalized Stabilities of Functional Equations via Isometries
The main goal of this research article is to investigate the stability of generalized norm-additive functional equations. This study demonstrates that these equations are Hyers-Ulam stable for surjective functions from an arbitrary group G to a real Banach space B using the large perturbation method. Furthermore, hyperstability results are investigated for a generalized Cauchy equation.
- 1 June 2024
- Published by Springer Nature in The Journal of Analysis
- Vol. 32 (6) , 3185-3195
Stability of a generalized Euler–Lagrange radical multifarious functional equation
- 1 June 2024
- Published by Springer Nature in The Journal of Analysis
- Vol. 32 (6) , 3185-3195
Stability of a generalized Euler–Lagrange radical multifarious functional equation
- Open Access
- 10 January 2023
- Published by MDPI AG in Mathematics
- Vol. 11 (2) , 371
Ulam Stability Results of Functional Equations in Modular Spaces and 2-Banach Spaces
In this work, we investigate the refined stability of the additive, quartic, and quintic functional equations in modular spaces with and without the -condition using the direct method (Hyers method). We also examine Ulam stability in 2-Banach space using the direct method. Additionally, using a suitable counterexample, we eventually demonstrate that the stability of these equations fails in a certain case.- 10 January 2023
- Published by MDPI AG in Mathematics
- Vol. 11 (2) , 371
Open AccessUlam Stability Results of Functional Equations in Modular Spaces and 2-Banach Spaces
In this work, we investigate the refined stability of the additive, quartic, and quintic functional equations in modular spaces with and without the -condition using the direct method (Hyers method). We also examine Ulam stability in 2-Banach space using the direct method. Additionally, using a suitable counterexample, we eventually demonstrate that the stability of these equations fails in a certain case. - Open Access
- 10 November 2022
- Published by SCIK Publishing Corporation in European Journal of Mathematical Analysis
- Vol. 3, 7
A Note on the Stability of Functional Equations via a Celebrated Direct Method
More than ten years after Justyna Sikorska [8] attempted to solve the Heyers-Ulam stability of a single variable equation by using direct method. In this paper, we will improve the results of Justyna Sikorska by using a more efficient approach. Relations between the generalized functional equation, the dependence of their different parameters and several properties are also further explored. To achieve the problem, we try to develop some new techniques to overcome the fundamental difficulties caused by the different properties of the function and the presence of several variables in the equation. Furthermore, we continue to construct and study a couple of functional equations by making a new direct method.
- 10 November 2022
- Published by SCIK Publishing Corporation in European Journal of Mathematical Analysis
- Vol. 3, 7
Open AccessA Note on the Stability of Functional Equations via a Celebrated Direct Method
More than ten years after Justyna Sikorska [8] attempted to solve the Heyers-Ulam stability of a single variable equation by using direct method. In this paper, we will improve the results of Justyna Sikorska by using a more efficient approach. Relations between the generalized functional equation, the dependence of their different parameters and several properties are also further explored. To achieve the problem, we try to develop some new techniques to overcome the fundamental difficulties caused by the different properties of the function and the presence of several variables in the equation. Furthermore, we continue to construct and study a couple of functional equations by making a new direct method.
- Open Access
- 1 November 2022
- Published by Walter de Gruyter GmbH in Tatra Mountains Mathematical Publications
- Vol. 81 (1) , 81-88
Stabilities and Non-Stabilities of a New Reciprocal Functional Equation
Sciendo provides publishing services and solutions to academic and professional organizations and individual authors. We publish journals, books, conference proceedings and a variety of other publications.
- 1 November 2022
- Published by Walter de Gruyter GmbH in Tatra Mountains Mathematical Publications
- Vol. 81 (1) , 81-88
Open AccessStabilities and Non-Stabilities of a New Reciprocal Functional Equation
Sciendo provides publishing services and solutions to academic and professional organizations and individual authors. We publish journals, books, conference proceedings and a variety of other publications.
- Open Access
- 5 April 2022
- Published by MDPI AG in Mathematics
- Vol. 10 (7) , 1188
The Stability of Functional Equations with a New Direct Method
We investigate the Hyers–Ulam stability of an equation involving a single variable of the form where f is an unknown operator from a nonempty set X into a Banach space Y, and it preserves the addition operation, besides other certain conditions. The theory is employed and stability theorems are proven for various functional equations involving several variables. By comparing this method with the available techniques, it was noticed that this method does not require any restriction on the parity, on the domain, and on the range of the function. Our findings suggest that it is very much easy and more appropriate to apply the proposed method while investigating the stability of functional equations, in particular for several variables.- 5 April 2022
- Published by MDPI AG in Mathematics
- Vol. 10 (7) , 1188
Open AccessThe Stability of Functional Equations with a New Direct Method
We investigate the Hyers–Ulam stability of an equation involving a single variable of the form where f is an unknown operator from a nonempty set X into a Banach space Y, and it preserves the addition operation, besides other certain conditions. The theory is employed and stability theorems are proven for various functional equations involving several variables. By comparing this method with the available techniques, it was noticed that this method does not require any restriction on the parity, on the domain, and on the range of the function. Our findings suggest that it is very much easy and more appropriate to apply the proposed method while investigating the stability of functional equations, in particular for several variables. - Open Access
- 28 November 2021
- Published by MDPI AG in Mathematics
- Vol. 9 (23) , 3063
Ulam Stabilities and Instabilities of Euler–Lagrange-Rassias Quadratic Functional Equation in Non-Archimedean IFN Spaces
In this paper, we use direct and fixed-point techniques to examine the generalised Ulam–Hyers stability results of the general Euler–Lagrange quadratic mapping in non-Archimedean IFN spaces (briefly, non-Archimedean Intuitionistic Fuzzy Normed spaces) over a field.
- 28 November 2021
- Published by MDPI AG in Mathematics
- Vol. 9 (23) , 3063
Open AccessUlam Stabilities and Instabilities of Euler–Lagrange-Rassias Quadratic Functional Equation in Non-Archimedean IFN Spaces
In this paper, we use direct and fixed-point techniques to examine the generalised Ulam–Hyers stability results of the general Euler–Lagrange quadratic mapping in non-Archimedean IFN spaces (briefly, non-Archimedean Intuitionistic Fuzzy Normed spaces) over a field.
- Open Access
- 13 February 2021
- Published by Wiley in Journal of Function Spaces
- Vol. 2021, 1-7
Orthogonal Stability and Nonstability of a Generalized Quartic Functional Equation in Quasi-β-Normed Spaces
In this work, we examine the generalized Hyers-Ulam orthogonal stability of the quartic functional equation in quasi--normed spaces. Moreover, we prove that this functional equation is not stable in a special condition by a counterexample.
- 13 February 2021
- Published by Wiley in Journal of Function Spaces
- Vol. 2021, 1-7
Open AccessOrthogonal Stability and Nonstability of a Generalized Quartic Functional Equation in Quasi-β-Normed Spaces
In this work, we examine the generalized Hyers-Ulam orthogonal stability of the quartic functional equation in quasi--normed spaces. Moreover, we prove that this functional equation is not stable in a special condition by a counterexample.