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Full-Text Articles in Physical Sciences and Mathematics

A Parametric Family Of Ternary Purely Exponential Diophantine Equation $A^X+B^Y=C^Z$, Yasutsugu Fujita, Maohua Le Jan 2022

A Parametric Family Of Ternary Purely Exponential Diophantine Equation $A^X+B^Y=C^Z$, Yasutsugu Fujita, Maohua Le

Turkish Journal of Mathematics

Let $a,b,c$ be fixed positive integers such that $a+b=c^2$, $2 \nmid c$ and $(b/p)\ne 1$ for every prime divisor $p$ of $c$, where $(b/p)$ is the Legendre symbol. Further let $m$ be a positive integer with $m>1$. In this paper, using the Baker method, we prove that if $m>\max\{10^8,c^2\}$, then the equation $(am^2+1)^x+(bm^2-1)^y=(cm)^z$ has only one positive integer solution $(x,y,z)=(1,1,2)$.


Clairaut Semi-Invariant Riemannian Maps From Almost Hermitian Manifolds, Sushil Kumar, Rajendra Prasad, Sumeet Kumar Jan 2022

Clairaut Semi-Invariant Riemannian Maps From Almost Hermitian Manifolds, Sushil Kumar, Rajendra Prasad, Sumeet Kumar

Turkish Journal of Mathematics

In this article, we define Clairaut semi-invariant Riemannian maps (CSIR Maps, In short) from almost Hermitian manifolds onto Riemannian manifolds and investigate fundamental results on such maps. We also obtain conditions for totally geodesicness on distributions defined in the introduced notion. Moreover, we provide an explicit example of CSIR map.


On Elastic Graph Spines Associated To Quadratic Thurston Maps, Meli̇ke Yeti̇şer, Ali̇ Berkay Yeti̇şer Jan 2022

On Elastic Graph Spines Associated To Quadratic Thurston Maps, Meli̇ke Yeti̇şer, Ali̇ Berkay Yeti̇şer

Turkish Journal of Mathematics

For a quadratic Thurston map having two distinct critical points and $n$ postcritical points, we count the number of possible dynamical portraits. We associate elastic graph spines to several hyperbolic quadratic Thurston rational functions. These functions have four postcritical points, real coefficients, and invariant real intervals. The elastic graph spines are constructed such that each has embedding energy less than one. These are supporting examples to Dylan Thurston's recent positive characterization of rational maps. Using the same characterization, we prove that with a combinatorial restriction on the branched covering and a cycle condition on the dynamical portrait, a quadratic Thurston …


Inverse Coefficient Identification Problem For A Hyperbolic Equation With Nonlocal Integral Condition, Azizbayov Elvin Jan 2022

Inverse Coefficient Identification Problem For A Hyperbolic Equation With Nonlocal Integral Condition, Azizbayov Elvin

Turkish Journal of Mathematics

This paper is concerned with an inverse coefficient identification problem for a hyperbolic equation in a rectangular domain with a nonlocal integral condition. We introduce the definition of the classical solution, and then the considered problem is reduced to an auxiliary equivalent problem. Further, the existence and uniqueness of the solution of the equivalent problem are proved using a contraction mapping principle. Finally, using equivalency, the unique existence of a classical solution is proved.


On The Convergence Of The Abel-Poisson Means Of Multiple Fourier Series, Si̇nem Sezer, Meli̇h Eryi̇ği̇t, Si̇mten Bayrakçi Jan 2022

On The Convergence Of The Abel-Poisson Means Of Multiple Fourier Series, Si̇nem Sezer, Meli̇h Eryi̇ği̇t, Si̇mten Bayrakçi

Turkish Journal of Mathematics

Let $ A_\varepsilon (x,f)$ be the Abel-Poisson means of an integrable function $f(x)$ on $n$-dimensional torus $ \mathbf{T}^n, \; \;\; i= 1,\ldots,n \; (n\geq 2) $ in the Euclidean $n$-space. The famous Bochner's theorem asserts that for any function $ f\in L^1(\mathbf{T}^n)$ the Abel-Poisson means $A_\varepsilon (x,f)$ are pointwise converge to $f(x)$ a.e., that is, $$ \underset{\varepsilon \rightarrow0^+}{\lim}\, A_\varepsilon (x,f)= f(x), \;\; a.e.\; x\in \mathbf{T}^n. $$ In this paper we investigate the rate of convergence of Abel-Poisson means at the so-called $\mu$-smoothness point of $f$ .


An Application Of Modified Sigmoid Function To A Class Of $Q-$ Starlike And $Q-$ Convex Analytic Error Functions, Arzu Akgül Jan 2022

An Application Of Modified Sigmoid Function To A Class Of $Q-$ Starlike And $Q-$ Convex Analytic Error Functions, Arzu Akgül

Turkish Journal of Mathematics

In this study, in the open unit disc $\Lambda$, by applying the $q-$ derivative operator and the fractional $q-$ derivative operator and by using the principle of subordination between analytic functions, we introduce some new interesting subclasses of $q-$ starlike and $q-$ convex analytic functions associated with error functions and modified sigmoid functions.


Study Of The $\Phi$-Generalized Type $K$-Fractional Integrals Or Derivatives And Some Of Their Properties, Mustafa Aydin, Nazim I. Mahmudov Jan 2022

Study Of The $\Phi$-Generalized Type $K$-Fractional Integrals Or Derivatives And Some Of Their Properties, Mustafa Aydin, Nazim I. Mahmudov

Turkish Journal of Mathematics

A novel fractional integral in the sense of Riemann-Liouville integral and two new fractional derivatives in the sense of Riemann-Liouville derivative and Caputo derivative with respect to another function and two parameters are introduced. Some significant properties of them are presented like semigroup property, inverse property, etc. The solution of the Cauchy-type problem for the nonhomogenous linear differential equation with the $\phi$-generalized Caputo $k$-fractional derivative is given by using the method of successive approximation.


Quasilinear Systems With Unpredictable Relay Perturbations, Mehmet Onur Fen, Fatma Fen Jan 2022

Quasilinear Systems With Unpredictable Relay Perturbations, Mehmet Onur Fen, Fatma Fen

Turkish Journal of Mathematics

It is rigorously proven under certain assumptions that a quasilinear system with discontinuous right-hand side possesses a unique unpredictable solution. The discontinuous perturbation function on the right-hand side is defined by means of an unpredictable sequence. A Gronwall-Coppel type inequality is utilized to achieve the main result, and the stability of the unpredictable solution is discussed. Examples with exponentially asymptotically stable and unstable unpredictable solutions are provided.


Arf Numerical Semigroups With Multiplicity $11$ And $13$, Hali̇l İbrahi̇m Karakaş, Sedat İlhan, Meral Süer Jan 2022

Arf Numerical Semigroups With Multiplicity $11$ And $13$, Hali̇l İbrahi̇m Karakaş, Sedat İlhan, Meral Süer

Turkish Journal of Mathematics

Parametrizations are given for Arf numerical semigroups with multiplicity up to 10. In this work, we give parametrizations of Arf numerical semigroups with multiplicity $11$ and $13$, and combining these results with previous results about the number of Arf numerical semigroups with multiplicity $2, 3, 5, 7$, we share some observations about the set of Arf numerical semigroups with prime multiplicity.


Some Relations Between Almost Paracontact Metric Manifolds And Almost Parahermitian Manifolds, Nüli̇fer Özdemi̇r, Neci̇p Erdoğan Jan 2022

Some Relations Between Almost Paracontact Metric Manifolds And Almost Parahermitian Manifolds, Nüli̇fer Özdemi̇r, Neci̇p Erdoğan

Turkish Journal of Mathematics

In this study, almost paracontact metric manifolds and almost para-Hermitian manifolds are considered. The relations between almost paracontact metric manifolds and almost para-Hermitian manifolds are investigated and certain results are acquired. Examples of almost para-Hermitian manifolds are presented using the determined relations.


Induced Polynomial Structures On Generalized Geometry, Fernando Etayo, Pablo Gomez Nicolas, Rafael Santamaria Jan 2022

Induced Polynomial Structures On Generalized Geometry, Fernando Etayo, Pablo Gomez Nicolas, Rafael Santamaria

Turkish Journal of Mathematics

In this paper, we study different geometric structures that can be defined as section endomorphisms of the generalized tangent bundle $\mathbb TM := TM\oplus T^*M\to M$. This vector bundle admits some structures that arise canonically and other that can be induced from geometric structures defined on the manifold. We comment some well-known examples and present new structures, focusing on the polynomial structures that can be induced in the generalized tangent bundle.


Univalence Criteria For Analytic Functions Obtained Using Fuzzydifferential Subordinations, Georgia Irina Oros Jan 2022

Univalence Criteria For Analytic Functions Obtained Using Fuzzydifferential Subordinations, Georgia Irina Oros

Turkish Journal of Mathematics

Ever since Lotfi A. Zadeh published the paper "Fuzzy Sets" in 1965 setting the basis of a new theory named fuzzy sets theory, many scientists have developed this theory and its applications. Mathematicians were especially interested in extending classical mathematical results in the fuzzy context. Such an extension was also done relating fuzzy sets theory and geometric theory of analytic functions. The study begun in 2011 has many interesting published outcomes and the present paper follows the line of the previous research in the field. The aim of the paper is to give some references related to the connections already …


On Slack $2$-Geodesic Convex Set And Geodesic $E$-Pseudoconvex Function With Application, Akhlad Iqbal, Praveen Kumar, Izhar Ahmad Jan 2022

On Slack $2$-Geodesic Convex Set And Geodesic $E$-Pseudoconvex Function With Application, Akhlad Iqbal, Praveen Kumar, Izhar Ahmad

Turkish Journal of Mathematics

We introduce a new class of sets named, slack $2$-geodesic convex set on Riemannian manifolds and verify by a nontrivial example. We define a geodesic $E$-pseudoconvex function with a suitable example. Some properties of geodesic $E$-quasiconvex function are discussed. We establish some relationships between slack $2$-geodesic convex set, geodesic $E$-pseudoconvex function and geodesic $E$-quasiconvex function. Moreover, an application of geodesic $E$-quasiconvex function to a nonlinear programming problem is also presented.


Formal Categorical Reasoning, Burak Eki̇ci̇ Jan 2022

Formal Categorical Reasoning, Burak Eki̇ci̇

Turkish Journal of Mathematics

In this paper, we present a category theory library developed in the proof assistant Coq. We discuss the design principles of the library in comparison with those existing out there. To explicitly demonstrate the utility of the library, we conclude with a case study in which a Coq formalized soundness proof of the intuitionistic propositional logic within a category theoretical settings is examined.


A Series Evaluation Technique Based On A Modified Abel Lemma, John Maxwell Campbell, Marco Cantarini Jan 2022

A Series Evaluation Technique Based On A Modified Abel Lemma, John Maxwell Campbell, Marco Cantarini

Turkish Journal of Mathematics

We introduce a technique for determining infinite series identities through something of a combination of the modified Abel lemma on summation by parts and a method of undetermined coefficients. We succeed in applying our technique in our proving a nontrivial variant of Gauss' hypergeometric identity, giving us an evaluation for a family of ${}_{3}F_{2}(1)$-series with three free parameters, and to establish a ${}_{3}F_{2}(-1)$-variant of Kummer's hypergeometric identity. Also, we apply the technique upon which this article is based to formulate a new and simplified proof of a remarkable series evaluation recently derived by Cantarini via the generalized Clebsch-Gordan integral.


Sequences Of Polynomials Satisfying The Pascal Property, Tuangrat Chaichana, Vichian Laohakosol, Rattiya Meesa Jan 2022

Sequences Of Polynomials Satisfying The Pascal Property, Tuangrat Chaichana, Vichian Laohakosol, Rattiya Meesa

Turkish Journal of Mathematics

Since one of the most important properties of binomial coefficients is the Pascal's triangle identity (referred to as the Pascal property) and since the sequence of binomial polynomials forms a regular basis for integer-valued polynomials, it is natural to ask whether the Pascal property holds in some more general setting, and what types of integer-valued polynomials possess the Pascal property. After defining the general Pascal property, a sequence of polynomials which satisfies the Pascal property is characterized with the classical case as an example. In connection with integer-valued polynomials, characterizations are derived for a sequence of polynomials which satisfies the …


A Class Of Finsler Measure Spaces Of Constant Weighted Ricci Curvature, Songting Yin, Xiaohuan Mo, Ling Zhu Jan 2022

A Class Of Finsler Measure Spaces Of Constant Weighted Ricci Curvature, Songting Yin, Xiaohuan Mo, Ling Zhu

Turkish Journal of Mathematics

The weight Ricci curvature plays an important role in studying global Finsler geometry. In this paper, we study a class of Finsler measure spaces of constant weighted Ricci curvature. We explicitly construct new families of such complete Finsler measure spaces. In particular, we find an eigenfunction and its eigenvalue for such spaces, generalizing a result previously only known in the case of Gaussian shrinking soliton. Finally, we give necessary and sufficient conditions on the coordinate functions for these spaces to be Euclidean measure spaces.


Symmetric Polynomials In Free Associative Algebras, Silvia Boumova, Vesselin Drensky, Deyan Dzhundrekov, Martin Kassabov Jan 2022

Symmetric Polynomials In Free Associative Algebras, Silvia Boumova, Vesselin Drensky, Deyan Dzhundrekov, Martin Kassabov

Turkish Journal of Mathematics

By a result of Margarete Wolf in 1936, we know that the algebra $K\langle X_d\rangle^{Sym(d)}$ of symmetric polynomials in noncommuting variables is not finitely generated. In 1984, Koryukin proved that if we equip the homogeneous component of degree $n$ with the additional action of $Sym(n)$ by permuting the positions of the variables, then the algebra of invariants $K\langle X_d\rangle^G$ of every reductive group $G$ is finitely generated. First, we make a short comparison between classical invariant theory of finite groups and its noncommutative counterpart. Then, we expose briefly the results of Wolf. Finally, we present the main result of our …


Tensor Products Of Graded-Simple $\Mathfrak{Sl}_2(\Mathbb{C})$-Modules, Yuri Bahturin, Abdallah Shihadeh Jan 2022

Tensor Products Of Graded-Simple $\Mathfrak{Sl}_2(\Mathbb{C})$-Modules, Yuri Bahturin, Abdallah Shihadeh

Turkish Journal of Mathematics

In our paper [3] we have constructed the first example of simple graded torsion-free $\mathfrak{sl}_2(\mathbb{C})$-module denoted by $ M^{C}_{λ}$. Here we examine tensor product of $ M^{C}_{λ}$ with finite dimensional simple $\mathfrak{sl}_2(\mathbb{C})$-modules.


$Gl_N$-Invariant Functions On $M_N(\Mathcal{G})$, Alan Berele Jan 2022

$Gl_N$-Invariant Functions On $M_N(\Mathcal{G})$, Alan Berele

Turkish Journal of Mathematics

We describe the $GL_n(F)$-invariant functions on $M_n(\mathcal{G})$ (where $\mathcal{G}$ is the infinite dimensional Grassmann algebra) and show that not all of them are trace polynomials, if $n\ge3$


Jordan Maps And Zero Lie Product Determined Algebras, Matej Bresar Jan 2022

Jordan Maps And Zero Lie Product Determined Algebras, Matej Bresar

Turkish Journal of Mathematics

Let $A$ be an algebra over a field $F$ with $(F)\ne 2$. If $A$ is generated as an algebra by $[[A,A],[A,A]]$, then for every skew-symmetric bilinear map $\Phi:A\times A\to X$, where $X$ is an arbitrary vector space over $F$, the condition that $\Phi(x^2,x)=0 $ for all $x\in A$ implies that $\Phi(xy,z) +\Phi(zx,y) + \Phi(yz,x)=0$ for all $x,y,z\in A$. This is applicable to the question of whether $A$ is zero Lie product determined and is also used in proving that a Jordan homomorphism from $A$ onto a semiprime algebra $B$ is the sum of a homomorphism and an antihomomorphism.


Invariants Of Symplectic And Orthogonal Groups Acting On $Gl(N,Cc)$-Modules, Vesselin Drensky, Elitza Hristova Jan 2022

Invariants Of Symplectic And Orthogonal Groups Acting On $Gl(N,Cc)$-Modules, Vesselin Drensky, Elitza Hristova

Turkish Journal of Mathematics

Let $GL(n) = GL(n, CC)$ denote the complex general linear group and let $G \subset GL(n)$ be one of the classical complex subgroups $OO(n)$, $SO(n)$, and $Sp(2k)$ (in the case $n = 2k$). We take a finite dimensional polynomial $GL(n)$-module $W$ and consider the symmetric algebra $S(W)$. Extending previous results for $G=SL(n)$, we develop a method for determining the Hilbert series $H(S(W)^G, t)$ of the algebra of invariants $S(W)^G$. Our method is based on simple algebraic computations and can be easily realized using popular software packages. Then we give many explicit examples for computing $H(S(W)^G, t)$. As an application, we …


Symmetric Polynomials In The Free Metabelian Associative Algebra Of Rank 2, Şehmus Findik Jan 2022

Symmetric Polynomials In The Free Metabelian Associative Algebra Of Rank 2, Şehmus Findik

Turkish Journal of Mathematics

Let $F$ be the free metabelian associative algebra generated by $x$ and $y$ over a field of characteristic zero. We call a polynomial $f\in F$ symmetric, if $f(x,y)=f(y,x)$. The set of all symmetric polynomials coincides with the algebra $F^{S_2}$ of invariants of the symmetric group $S_2$. In this paper, we give the full description of the algebra $F^{S_2}$.


A Variant Of Rosset's Approach To The Amitsur-Levitzki Theorem And Some $\Mathbb{Z}_{2}$-Graded Identities Of $\Mathrm{M}_{N}(E)$, Szilvia Homolya, Jen Szigeti Jan 2022

A Variant Of Rosset's Approach To The Amitsur-Levitzki Theorem And Some $\Mathbb{Z}_{2}$-Graded Identities Of $\Mathrm{M}_{N}(E)$, Szilvia Homolya, Jen Szigeti

Turkish Journal of Mathematics

In the spirit of Rosset's proof of the Amitsur-Levitzki theorem, we show how the standard identiy (for matrices over a commutative base ring) and the addition of external Grassmann variables can be used to derive a certain $\mathbb{Z}_{2}$-graded polynomial identity of $\mathrm{M}_{n}(E)$.


Polynomial Identities In Matrix Algebras With Pseudoinvolution, Antonio Ioppolo Jan 2022

Polynomial Identities In Matrix Algebras With Pseudoinvolution, Antonio Ioppolo

Turkish Journal of Mathematics

Let $F$ be an algebraically closed field of characteristic zero. In this paper we deal with matrix superalgebras (i.e. algebras graded by $\mathbb{Z}_2$, the cyclic group of order $2$) endowed with a pseudoinvolution. The first goal is to present the classification of the pseudoinvolutions that it is possible to define, up to equivalence, in the full matrix algebra $M_n(F)$ of $n \times n$ matrices and on its subalgebra $UT_n(F)$ of upper-triangular matrices. Along the way we shall give the generators of the $T$-ideal of identities for the algebras $M_2(F)$, $UT_2(F)$ and $UT_3(F)$, endowed with all possible inequivalent pseudoinvolutions.


On Central Polynomials And Codimension Growth, Fabrizio Martino Jan 2022

On Central Polynomials And Codimension Growth, Fabrizio Martino

Turkish Journal of Mathematics

Let $A$ be an associative algebra over a field of characteristic zero. A central polynomial is a polynomial of the free associative algebra that takes central values of $A.$ In this survey, we present some recent results about the exponential growth of the central codimension sequence and the proper central codimension sequence in the setting of algebras with involution and algebras graded by a finite group.


A New Approach To Word Standardization And Some Of Its Applications, Wesam Talab Jan 2022

A New Approach To Word Standardization And Some Of Its Applications, Wesam Talab

Turkish Journal of Mathematics

In this article, we study word standardization in comparison to Young tableau standardization. We count the number of words (respectively Young tableau) standardized to a given permutation (respectively to a given standard Young tableau). We prove that both rectification and standardization applications commute and show that the standardization commutes with the insertion of Robinson--Schensted. We show that the standardizations of Knuth-equivalent two words are also Knuth equivalent. Finally, using word standardization we establish a proof for the following well-known equality: $$ \forall l \in \left\lbrace 0,1,\ldots,n-1\right\rbrace ,~~\left \langle {n\atop l} \right \rangle=d_{n,l}=a_{n,l}= \sum_{0\leq k \leq l}(-1)^k { n+1 \choose k …


On The Restricted Graded Jacobson Radical Of Rings Of Morita Context, Puguh Wahyu Prasetyo, Hidetoshi Marubayashi, Indah Emilia Wijayanti Jan 2022

On The Restricted Graded Jacobson Radical Of Rings Of Morita Context, Puguh Wahyu Prasetyo, Hidetoshi Marubayashi, Indah Emilia Wijayanti

Turkish Journal of Mathematics

The class of rings $\mathcal{J}=\{A (A,\circ)$ forms a group$\}$ forms a radical class and it is called the Jacobson radical class. For any ring $A$, the Jacobson radical $\mathcal{J}(A)$ of $A$ is defined as the largest ideal of $A$ which belongs to $\mathcal{J}$. In fact, the Jacobson radical is one of the most important radical classes since it is used widely in another branch of abstract algebra, for example, to construct a two-sided brace. On the other hand, for every ring of Morita context $T=\begin{pmatrix} R & V \\ W & S \end{pmatrix}$, we will show directly by the structure …


Nilpotent Varieties And Metabelian Varieties, Angela Valenti, Sergey Mishchenko Jan 2022

Nilpotent Varieties And Metabelian Varieties, Angela Valenti, Sergey Mishchenko

Turkish Journal of Mathematics

We deal with varieties of nonassociative algebras having polynomial growth of codimensions. We describe some results obtained in recent years in the class of left nilpotent algebras of index two. Recently the authors established a correspondence between the growth rates for left nilpotent algebras of index two and the growth rates for commutative or anticommutative metabelian algebras that allows to transfer the results concerning varieties of left nilpotent algebras of index two to varieties of commutative or anticommutative metabelian algebras.


Analyzing Bifurcation, Stability, And Chaos Control For A Discrete-Time Prey-Predator Model With Allee Effect, Fi̇gen Kangalgi̇l, Ni̇lüfer Topsakal, Ni̇hal Öztürk Jan 2022

Analyzing Bifurcation, Stability, And Chaos Control For A Discrete-Time Prey-Predator Model With Allee Effect, Fi̇gen Kangalgi̇l, Ni̇lüfer Topsakal, Ni̇hal Öztürk

Turkish Journal of Mathematics

In this paper, the qualitative behavior of a discrete-time prey-predator model with Allee effect in prey population is discussed. Firstly, the existence of the fixed points and their topological classification are analyzed algebraically. Then, the conditions of existence for both period-doubling and Neimark--Sacker bifurcations arising from coexistence fixed point with the help of the center manifold theorem and bifurcation theory are investigated. OGY feedback control method is implemented to control chaos in the proposed model due to the emergence of bifurcations. Finally, numerical simulations are performed to support the theoretical findings.