In this paper,we define a new class of control functions through aggregate special functions.These class of control functions help us to stabilize and approximate a tri-additiveψ-functional inequality to get a better...In this paper,we define a new class of control functions through aggregate special functions.These class of control functions help us to stabilize and approximate a tri-additiveψ-functional inequality to get a better estimation for permuting tri-homomorphisms and permuting tri-derivations in unital C*-algebras and Banach algebras by the vector-valued alternative fixed point theorem.展开更多
In this paper, we introduce the concept of generalized g-quasi-contractions in the setting of cone b-metric spaces over Banach algebras. By omitting the assump- tion of normality we establish common fixed point theore...In this paper, we introduce the concept of generalized g-quasi-contractions in the setting of cone b-metric spaces over Banach algebras. By omitting the assump- tion of normality we establish common fixed point theorems for the generalized g- quasi-contractions with the spectral radius r(λ) of the g-quasi-contractive constant vector λ satisfying r(λ) ∈[0,1) in the setting of cone b-metric spaces over Banach al- gebras, where the coefficient s satisfies s ≥ 1. The main results generalize, extend and unify several well-known comparable results in the literature.展开更多
The invariant determinants ha Banach algebras are discussed and a necessary and sufficient condition for those integral traced unital Barach algebra(A,τ) admitting a G-invari- ant determinant is obtained,where G is a...The invariant determinants ha Banach algebras are discussed and a necessary and sufficient condition for those integral traced unital Barach algebra(A,τ) admitting a G-invari- ant determinant is obtained,where G is a group of trace preserving automorphisms of A.展开更多
The goal of the present paper is to investigate some new HUR-stability results by applying the alternative fixed point of generalized quartic functional equationin β-Banach modules on Banach algebras. The concept of ...The goal of the present paper is to investigate some new HUR-stability results by applying the alternative fixed point of generalized quartic functional equationin β-Banach modules on Banach algebras. The concept of Ulam-Hyers-Rassias stability (briefly, HUR-stability) originated from Th. M. Rassias stability theorem that appeared in his paper: On the stability of the linear mapping in Banach spaces, Proc. Amer. Math. Soc. 72 (1978), 297-300.展开更多
Let A and B be Banach algebras.Let M be a Banach A,B module with bounded 1.Then T=AM 0B is a Banach algebra with the usual operations and the norm AM 0B=‖A‖+‖M‖+‖B‖.Such an algebra is called a triangular Bana...Let A and B be Banach algebras.Let M be a Banach A,B module with bounded 1.Then T=AM 0B is a Banach algebra with the usual operations and the norm AM 0B=‖A‖+‖M‖+‖B‖.Such an algebra is called a triangular Banach algebra.In this paper the isometric isomorphisms of triangular Banach algebras are characterized.展开更多
For a Banach algebra A, we denote by .A* and .A** the first and the second duals of A respectively. Let T be a mapping from .A* to itself. In this article, we will investigate some stability results concerning the...For a Banach algebra A, we denote by .A* and .A** the first and the second duals of A respectively. Let T be a mapping from .A* to itself. In this article, we will investigate some stability results concerning the equations T(αf + βg) -= αT(f) + βT(g), T(af) = aT(f) andT(αf +βg) + T(αf - βg) =- 2α2T(f) + 2β2T(g) where f, g e .A*, a ∈ A, and α,β ∈ Q / {0}.展开更多
In this paper, we obtain a class of common fixed point theorems for generalized Lipschitz mappings in cone metric spaces with Banach algebras without the assumption of normality of cones. The results greatly generaliz...In this paper, we obtain a class of common fixed point theorems for generalized Lipschitz mappings in cone metric spaces with Banach algebras without the assumption of normality of cones. The results greatly generalize some results in the literature. Moreover,we give an example to support the main assertions.展开更多
We shall generalize the results of [9] about characterization of isomorphisms on quasi-Banach algebras by providing integral type conditions. Also, we shall give some new results in this way and finally, give a result...We shall generalize the results of [9] about characterization of isomorphisms on quasi-Banach algebras by providing integral type conditions. Also, we shall give some new results in this way and finally, give a result about hybrid fixed point of two homomorphisms on quasi-Banach algebras.展开更多
In this paper,we obtain some tripled common random fixed point and tripled random fixed point theorems with several generalized Lipschitz constants in such spaces.We consider the obtained assertions without the assump...In this paper,we obtain some tripled common random fixed point and tripled random fixed point theorems with several generalized Lipschitz constants in such spaces.We consider the obtained assertions without the assumption of normality of cones.The presented results generalize some coupled common fixed point theorems in the existing literature.展开更多
The following problem in an OBA (ordered Banach algebra) has been studied by various authors: If a and b are positiveelements in an OBA such that 0 ≤ α ≤ b and ifb has a certain property, under what conditions d...The following problem in an OBA (ordered Banach algebra) has been studied by various authors: If a and b are positiveelements in an OBA such that 0 ≤ α ≤ b and ifb has a certain property, under what conditions does a inherit that property? This will be referred to as the domination problem. In this paper we will introduce absolute value |.| in an OBA and obtain results for the domination problem under the more general inequality |α| ≤|b|. We will show that these results are applicable to positive operators on a Banach lattice. Furthermore, it will be demonstrated that some known results for the domination problem in OBAs continue to hold true if 0 ≤ α≤ b is replaced by |a|≤|b|.展开更多
Let A be a Banach algebra with unit e and a,b,c∈A,Mc=(a c 0 b)∈M_(2)(A).The concepts of left and right generalized Drazin invertible of elements in a Banach algebra are proposed.A generalized Drazin spectrum of is d...Let A be a Banach algebra with unit e and a,b,c∈A,Mc=(a c 0 b)∈M_(2)(A).The concepts of left and right generalized Drazin invertible of elements in a Banach algebra are proposed.A generalized Drazin spectrum of is defined byσ_(gD)(α)={λ∈C:α-λe is not generalized Drazin invertible}.It is shown thatσ_(gD)(a)∪σ_(gD)(b)=σ_(gD)(M_(C))∪W_(2),where W_(g) is a union of certain holes σ_(gD) and W_(g)■σ_(gD)(a)∩σ_(gD)(b),or more finely.In addition,some properties of generalized Drazin spectrum of elements in a Banach algebra are studied.展开更多
In this paper,we consider the algebraic structure of derivative Hardy Spaces.By using the method of[6,12,15],we get the Duhamel product forming Banach algebra in derivative Hardy Spaces,and invertibility criterion,and...In this paper,we consider the algebraic structure of derivative Hardy Spaces.By using the method of[6,12,15],we get the Duhamel product forming Banach algebra in derivative Hardy Spaces,and invertibility criterion,and describe the extended eigenvalue of the integral operator V.We generalize the results in[1,2,6,11,16].展开更多
We show that every unital invertibility preserving linear map from a von Neumann algebra onto a semi-simple Banach algebra is a Jordan homomorphism;this gives an affirmative answer to a problem of Kaplansky for all vo...We show that every unital invertibility preserving linear map from a von Neumann algebra onto a semi-simple Banach algebra is a Jordan homomorphism;this gives an affirmative answer to a problem of Kaplansky for all von Neumann algebras.For a unital linear map Φ from a semi-simple complex Banach algebra onto another,we also show that the following statements are equivalent:(1) Φ is an homomorphism;(2)Φ is completely invertibility preserving;(3)Φ is 2-invertibility preserving.展开更多
In this paper, among other things, the author studies the weak^*-closed left translation invariant complemented subspace of semigroup algebras and group algebras. Also, the author studies the relationships between pr...In this paper, among other things, the author studies the weak^*-closed left translation invariant complemented subspace of semigroup algebras and group algebras. Also, the author studies the relationships between projections and amenability.展开更多
Let A be a noncommutative Banach algebra.Suppose there exists a continuous linear Jordan derivation D:A→A such that [D(x),x]D(x)[D(x),x]∈ rad(A) for all x ∈ A.In this case, D(A)rad(A).
Our first purpose in this paper is to provide necessary conditions for a weak*-closed translation invariant subspace in the semigroup algebra of a locally compact topological foundation semigroup to be completely com...Our first purpose in this paper is to provide necessary conditions for a weak*-closed translation invariant subspace in the semigroup algebra of a locally compact topological foundation semigroup to be completely complemented. We give conditions when a weak*-closed left translation invariant subspace in Ma,(S)* of a compact cancellative foundation semigroup S is the range of a weak*-weak* continuous projection on M~,(S)* commuting with translations. Let G be a locally compact group and A be a Banach G-module. Our second purpose in this paper is to study some projections on A* and /3(A*) which commutes with translations and convolution.展开更多
In this work,some new fixed point results for generalized Lipschitz mappings on generalized c-distance in cone b-metric spaces over Banach algebras are obtained,not acquiring the condition that the underlying cone sho...In this work,some new fixed point results for generalized Lipschitz mappings on generalized c-distance in cone b-metric spaces over Banach algebras are obtained,not acquiring the condition that the underlying cone should be normal or the mappings should be continuous.Furthermore,the existence and the uniqueness of the fixed point are proven for such mappings.These results greatly improve and generalize several well-known comparable results in the literature.Moreover,some examples and an application are given to support our new results.展开更多
Let R be a prime ring of characteristic different from 2 with Utumi quotientring U and extended centroid C,F and G,the two nonzero generalized derivationsof R,I an ideal of R and f(x1,...,xn)a multilinear polynomial o...Let R be a prime ring of characteristic different from 2 with Utumi quotientring U and extended centroid C,F and G,the two nonzero generalized derivationsof R,I an ideal of R and f(x1,...,xn)a multilinear polynomial over C which is notcentral valued on R.If F(G(f(x1,...,Xn))f(X1,...,Xn))=0 for all x1,...,Xn∈1,then one of the followings holds:(1)there exist a,b c Usuch that F(x)=ax and G(x)=bx for all x c R with ab=0;(2)there exista,b,p c U such that F(x)=ax+xb and G(x)=px for all x c R with F(p)=0and f(x1,...,xn)’is central valued on R.We also obtain some related results in caseswhere R is a semiprime ring and Banach algebra.展开更多
基金partially supported by the Natural Sciences and Engineering Research Council of Canada(2019-03907)。
文摘In this paper,we define a new class of control functions through aggregate special functions.These class of control functions help us to stabilize and approximate a tri-additiveψ-functional inequality to get a better estimation for permuting tri-homomorphisms and permuting tri-derivations in unital C*-algebras and Banach algebras by the vector-valued alternative fixed point theorem.
基金supported by the National Natural Science Foundation of China(No.11361064)the project No.174024 of the Ministry of Education,Science and Technological Department of the Republic of Serbia
文摘In this paper, we introduce the concept of generalized g-quasi-contractions in the setting of cone b-metric spaces over Banach algebras. By omitting the assump- tion of normality we establish common fixed point theorems for the generalized g- quasi-contractions with the spectral radius r(λ) of the g-quasi-contractive constant vector λ satisfying r(λ) ∈[0,1) in the setting of cone b-metric spaces over Banach al- gebras, where the coefficient s satisfies s ≥ 1. The main results generalize, extend and unify several well-known comparable results in the literature.
文摘A determinant theory is developed for Banach algebras and a characterization of those traced unital Banach algebras admitting a determinant is given.
文摘The invariant determinants ha Banach algebras are discussed and a necessary and sufficient condition for those integral traced unital Barach algebra(A,τ) admitting a G-invari- ant determinant is obtained,where G is a group of trace preserving automorphisms of A.
文摘The goal of the present paper is to investigate some new HUR-stability results by applying the alternative fixed point of generalized quartic functional equationin β-Banach modules on Banach algebras. The concept of Ulam-Hyers-Rassias stability (briefly, HUR-stability) originated from Th. M. Rassias stability theorem that appeared in his paper: On the stability of the linear mapping in Banach spaces, Proc. Amer. Math. Soc. 72 (1978), 297-300.
文摘Let A and B be Banach algebras.Let M be a Banach A,B module with bounded 1.Then T=AM 0B is a Banach algebra with the usual operations and the norm AM 0B=‖A‖+‖M‖+‖B‖.Such an algebra is called a triangular Banach algebra.In this paper the isometric isomorphisms of triangular Banach algebras are characterized.
文摘For a Banach algebra A, we denote by .A* and .A** the first and the second duals of A respectively. Let T be a mapping from .A* to itself. In this article, we will investigate some stability results concerning the equations T(αf + βg) -= αT(f) + βT(g), T(af) = aT(f) andT(αf +βg) + T(αf - βg) =- 2α2T(f) + 2β2T(g) where f, g e .A*, a ∈ A, and α,β ∈ Q / {0}.
基金Supported by the Science and Technology Research Project of the Education Department of Hubei Province(B2015137) Supported by the National Social Science Foundation of China(12BZS050)
文摘In this paper, we obtain a class of common fixed point theorems for generalized Lipschitz mappings in cone metric spaces with Banach algebras without the assumption of normality of cones. The results greatly generalize some results in the literature. Moreover,we give an example to support the main assertions.
文摘We shall generalize the results of [9] about characterization of isomorphisms on quasi-Banach algebras by providing integral type conditions. Also, we shall give some new results in this way and finally, give a result about hybrid fixed point of two homomorphisms on quasi-Banach algebras.
基金supported by the Foundation of Education Ministry,Hubei Province,China(Q20122203)
文摘In this paper,we obtain some tripled common random fixed point and tripled random fixed point theorems with several generalized Lipschitz constants in such spaces.We consider the obtained assertions without the assumption of normality of cones.The presented results generalize some coupled common fixed point theorems in the existing literature.
文摘The following problem in an OBA (ordered Banach algebra) has been studied by various authors: If a and b are positiveelements in an OBA such that 0 ≤ α ≤ b and ifb has a certain property, under what conditions does a inherit that property? This will be referred to as the domination problem. In this paper we will introduce absolute value |.| in an OBA and obtain results for the domination problem under the more general inequality |α| ≤|b|. We will show that these results are applicable to positive operators on a Banach lattice. Furthermore, it will be demonstrated that some known results for the domination problem in OBAs continue to hold true if 0 ≤ α≤ b is replaced by |a|≤|b|.
文摘Let A be a Banach algebra with unit e and a,b,c∈A,Mc=(a c 0 b)∈M_(2)(A).The concepts of left and right generalized Drazin invertible of elements in a Banach algebra are proposed.A generalized Drazin spectrum of is defined byσ_(gD)(α)={λ∈C:α-λe is not generalized Drazin invertible}.It is shown thatσ_(gD)(a)∪σ_(gD)(b)=σ_(gD)(M_(C))∪W_(2),where W_(g) is a union of certain holes σ_(gD) and W_(g)■σ_(gD)(a)∩σ_(gD)(b),or more finely.In addition,some properties of generalized Drazin spectrum of elements in a Banach algebra are studied.
基金Supported by National Natural Science Foundation of China(11801094).
文摘In this paper,we consider the algebraic structure of derivative Hardy Spaces.By using the method of[6,12,15],we get the Duhamel product forming Banach algebra in derivative Hardy Spaces,and invertibility criterion,and describe the extended eigenvalue of the integral operator V.We generalize the results in[1,2,6,11,16].
基金supported by NNSFC (10071046)PNSFS (981009)+1 种基金PYSFS(20031009)China Postdoctoral Science Foundation
文摘We show that every unital invertibility preserving linear map from a von Neumann algebra onto a semi-simple Banach algebra is a Jordan homomorphism;this gives an affirmative answer to a problem of Kaplansky for all von Neumann algebras.For a unital linear map Φ from a semi-simple complex Banach algebra onto another,we also show that the following statements are equivalent:(1) Φ is an homomorphism;(2)Φ is completely invertibility preserving;(3)Φ is 2-invertibility preserving.
文摘In this paper, among other things, the author studies the weak^*-closed left translation invariant complemented subspace of semigroup algebras and group algebras. Also, the author studies the relationships between projections and amenability.
基金The author has been supported by Kangnung National University,Research Fund,1998
文摘Let A be a noncommutative Banach algebra.Suppose there exists a continuous linear Jordan derivation D:A→A such that [D(x),x]D(x)[D(x),x]∈ rad(A) for all x ∈ A.In this case, D(A)rad(A).
文摘Our first purpose in this paper is to provide necessary conditions for a weak*-closed translation invariant subspace in the semigroup algebra of a locally compact topological foundation semigroup to be completely complemented. We give conditions when a weak*-closed left translation invariant subspace in Ma,(S)* of a compact cancellative foundation semigroup S is the range of a weak*-weak* continuous projection on M~,(S)* commuting with translations. Let G be a locally compact group and A be a Banach G-module. Our second purpose in this paper is to study some projections on A* and /3(A*) which commutes with translations and convolution.
基金partially supported by the Special Basic Cooperative Research Programs of Yunnan Provincial Undergraduate Universities'Association(grant No.202101BA070001-045).
文摘In this work,some new fixed point results for generalized Lipschitz mappings on generalized c-distance in cone b-metric spaces over Banach algebras are obtained,not acquiring the condition that the underlying cone should be normal or the mappings should be continuous.Furthermore,the existence and the uniqueness of the fixed point are proven for such mappings.These results greatly improve and generalize several well-known comparable results in the literature.Moreover,some examples and an application are given to support our new results.
基金The authors would like to thank the referee for providing shortened proof of Lemma2.1 in the paper.This work was done when the first author visited Ege University,TURKEY,from the9th June 2014 to the 15th June 2014 under the INSA-TUBA Exchange of Scientists Programme.The firstauthor is grateful to INSA,India and TUBA,Turkey for the financial support provided for this visit.
文摘Let R be a prime ring of characteristic different from 2 with Utumi quotientring U and extended centroid C,F and G,the two nonzero generalized derivationsof R,I an ideal of R and f(x1,...,xn)a multilinear polynomial over C which is notcentral valued on R.If F(G(f(x1,...,Xn))f(X1,...,Xn))=0 for all x1,...,Xn∈1,then one of the followings holds:(1)there exist a,b c Usuch that F(x)=ax and G(x)=bx for all x c R with ab=0;(2)there exista,b,p c U such that F(x)=ax+xb and G(x)=px for all x c R with F(p)=0and f(x1,...,xn)’is central valued on R.We also obtain some related results in caseswhere R is a semiprime ring and Banach algebra.