In this article, we prove the Hyers-Ulam-Rassias stability of the following Cauchy-Jensen functional inequality:‖f (x) + f (y) + 2f (z) + 2f (w)‖ ≤‖ 2f x + y2 + z + w ‖(0.1)This is applied to inv...In this article, we prove the Hyers-Ulam-Rassias stability of the following Cauchy-Jensen functional inequality:‖f (x) + f (y) + 2f (z) + 2f (w)‖ ≤‖ 2f x + y2 + z + w ‖(0.1)This is applied to investigate isomorphisms between C*-algebras, Lie C*-algebras and JC*-algebras, and derivations on C*-algebras, Lie C*-algebras and JC*-algebras, associated with the Cauchy-Jensen functional equation 2f (x + y/2 + z + w) = f(x) + f(y) + 2f(z) + 2f(w).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
Let L:=-△+V be the Schrodinger operator on R^(n)with n≥3,where V is a non-negative potential satisfying△^(-1)(V)∈L^(∞)(R^(n)).Let w be an L-harmonic function,determined by V,satisfying that there exists a positiv...Let L:=-△+V be the Schrodinger operator on R^(n)with n≥3,where V is a non-negative potential satisfying△^(-1)(V)∈L^(∞)(R^(n)).Let w be an L-harmonic function,determined by V,satisfying that there exists a positive constantδsuch that,for any x∈Rn,0<δ≤w(x)≤1.Assume that p(·):R^(n)→(0,1]is a variable exponent satisfying the globally log-Hölder continuous condition.In this article,the authors show that the mappings HL^(p)(·))(R^(n))■f■wf∈H^(p)(·)(R^(n))and HL^(p(·))(R^(n))■f■(-△)^(1/2)L^(-1/2)(f)∈H^(p(·))(R^(n))are isomorphisms between the variable Hardy spaces HL^(p(·))(R^(n)),associated with L,and the variable Hardy spaces H^(p(·))(R^(n)).展开更多
In this paper, we introduce a new approach to characterize the isomor-phisms of circulant digraphs. In terms of this method, we completely determine theisomorphic classes of circulant digraphs of degree 3. In particul...In this paper, we introduce a new approach to characterize the isomor-phisms of circulant digraphs. In terms of this method, we completely determine theisomorphic classes of circulant digraphs of degree 3. In particular, we characterizethose circulant digraphs of degree 3 which don't satisfy Adam's conjecture.展开更多
In this paper, we discuss some multiplicative preservers and give some characterizations of isomorphisms or conjugate isomorphisms on β(X), where β(X) denotes the algebra of all bounded linear operators on a Banach ...In this paper, we discuss some multiplicative preservers and give some characterizations of isomorphisms or conjugate isomorphisms on β(X), where β(X) denotes the algebra of all bounded linear operators on a Banach space X.展开更多
We prove that a certain eventually homological isomorphism between module categories induces triangle equivalences between their singularity categories,Gorenstein defect categories and stable categories of Gorenstein ...We prove that a certain eventually homological isomorphism between module categories induces triangle equivalences between their singularity categories,Gorenstein defect categories and stable categories of Gorenstein projective modules.Furthermore,we show that the Auslander-Reiten conjecture and the Gorenstein symmetry conjecture can be reduced by eventually homological isomorphisms.Applying these results to arrow removal and vertex removal,we describe the Gorenstein projective modules over some non-monomial algebras and verify the Auslander-Reiten conjecture for certain algebras.展开更多
Let N and M be nests on Banach spaces X and Y over the real or complex field F, respectively, with the property that if M ∈ M such that M_ =M, then M is complemented in Y. Let AlgN and AlgM be the associated nest alg...Let N and M be nests on Banach spaces X and Y over the real or complex field F, respectively, with the property that if M ∈ M such that M_ =M, then M is complemented in Y. Let AlgN and AlgM be the associated nest algebras. Assume that Ф : AlgN → AlgM is a bijective map. It is proved that, if dim X = ∞ and if there is a nontrivial element in N which is complemented in X, then Ф is Lie multiplicative (i.e. Ф([A, B]) = [Ф(A), Ф(B)] for all A, B ∈ AlgN) if and only if Ф has the form Ф(A) = TAT^-1 + τ(A) for all A ∈ AlgAN or Ф(A) = -TA^*T^-1 + τ(A) for all A ∈ AlgN, where T is an invertible linear or conjugate linear operator and τ : AlgN →FI is a map with τ([A, B]) = 0 for all A, B ∈ AlgN. The Lie multiplicative maps are also characterized for the case dim X 〈 ∞.展开更多
In this paper we give the following main results: (ⅰ) Let F(?) and G(?) be two free modules. Then F(?) and G(?) are semi-linearly isomorphic if and only if End F(?) and End G(?) are strictly isomorphic. (ⅱ) We give ...In this paper we give the following main results: (ⅰ) Let F(?) and G(?) be two free modules. Then F(?) and G(?) are semi-linearly isomorphic if and only if End F(?) and End G(?) are strictly isomorphic. (ⅱ) We give a new method to generalize the Bolla theorem in 1985 which gave a categorical description for isomorphism between End F(?) and End G(?). (ⅲ) The Wolfson theorem is a corollary of our theorem.展开更多
Let R and A be commutative rings with identity, and m and n be integers ≥3. Consider when and how an isomorphism E_m(R)E_n(A) can be lifted to an isomorphism between the corresponding Steinberg groups. It was proved ...Let R and A be commutative rings with identity, and m and n be integers ≥3. Consider when and how an isomorphism E_m(R)E_n(A) can be lifted to an isomorphism between the corresponding Steinberg groups. It was proved that, if E_m(R) is isomorphic to E_n(A) then m=n (cf. Ref. [1]). When n≥4, every isomorphism E_n(R)E_n(A) is of the standard type, and it can be naturally and uniquely lifted to an isomorphism from St_n(R) to St_n(A) (cf. Refs. [1] and [2]). However, the case n=3 is different from that n≥4,展开更多
1. Introduction Since O’Meara worked out the automorphisms of orthogonal groups Ωn(V) over fields in [4] by using well-known residual space method, many results about the isomorphisms and automorphisms of orthogonal...1. Introduction Since O’Meara worked out the automorphisms of orthogonal groups Ωn(V) over fields in [4] by using well-known residual space method, many results about the isomorphisms and automorphisms of orthogonal groups over integral domains have been achieved. Refer to O’Meara, Hahn for example. B. R. McDonald, in [12], determined the automorphisms of O(V) over local rings with 2 a unit by using involutions.展开更多
In this paper, we discuss the necessary and sufficient conditions in which there exist exceptional isomorphisms between E3(A) and E3(R) and between GL3(A) and GL3(R) for commutative rings A and R. A counterexa...In this paper, we discuss the necessary and sufficient conditions in which there exist exceptional isomorphisms between E3(A) and E3(R) and between GL3(A) and GL3(R) for commutative rings A and R. A counterexample shows that two rings that are not isomorphic may have isomorphic tinear groups. This partly solves an open problem posed at the conference on abstract homomorphisms of algebraic groupsrs.展开更多
By a ball-covering B of a Banach space X, we mean that it is a collection of open balls off the origin whose union contains the sphere of the unit ball of X. The space X is said to have a ball-covering property, if it...By a ball-covering B of a Banach space X, we mean that it is a collection of open balls off the origin whose union contains the sphere of the unit ball of X. The space X is said to have a ball-covering property, if it admits a ball-covering consisting of countably many balls. This paper, by constructing the equivalent norms on l~∞, shows that ball-covering property is not invariant under isomorphic mappings, though it is preserved under such mappings if X is a Gateaux differentiability space; presents that this property of X is not heritable by its closed subspaces; and the property is also not preserved under quotient mappings.展开更多
In this paper, we will prove that every derivation of completely distributive subspace lattice (CDS)algebras on Banach space is automatically continuous. This is new even in the Hilbert space case. As an application o...In this paper, we will prove that every derivation of completely distributive subspace lattice (CDS)algebras on Banach space is automatically continuous. This is new even in the Hilbert space case. As an application of this result, we obtain that every additive derivation of nest algebras on Banach spaces is inner. We will also prove that every isomorphism between nest algebras on Banach space is automatically continuous, and in addition, is spatial.展开更多
By considering the Galois action and the group action,we give the relation of two isomorphism character rings on the arbitrary field K with CharK = 0.Our results generalize Saksonov's theorem.
We will be mainly concerned with some important fiber spaces over Teichmuller spaces, including the Bers fiber space and Teichmuller curve, establishing an isomorphism theorem between 'punctured' Teichmuller c...We will be mainly concerned with some important fiber spaces over Teichmuller spaces, including the Bers fiber space and Teichmuller curve, establishing an isomorphism theorem between 'punctured' Teichmuller curves and determining the biholomorphic isomorphisms of these fiber spaces.展开更多
For integral table algebras with integral table basis T, we can consider integral R-algebra RT over a subring R of the ring of the algebraic integers. It is proved that an R-algebra isomorphism between two integral ta...For integral table algebras with integral table basis T, we can consider integral R-algebra RT over a subring R of the ring of the algebraic integers. It is proved that an R-algebra isomorphism between two integral table algebras must be an integral table algebra isomorphism if it is compatible with the so-called normalizings of the integral table algebras.展开更多
In this paper we propose the concept of generalized semi-Cayley graphs, which is a combination of semi-Cayley graphs and generalized Cayley graphs. We study the isomorphisms and automorphisms of generalized semi-Cayle...In this paper we propose the concept of generalized semi-Cayley graphs, which is a combination of semi-Cayley graphs and generalized Cayley graphs. We study the isomorphisms and automorphisms of generalized semi-Cayley graphs and other related properties.展开更多
The following problem is discussed: If μ is an AF-algebra, A and B are two C-algebras, x(A) and x(B) are the unit balls of μ A and μ B respectively, and there is an affine isomorphism from X(A) onto x(B), when are ...The following problem is discussed: If μ is an AF-algebra, A and B are two C-algebras, x(A) and x(B) are the unit balls of μ A and μ B respectively, and there is an affine isomorphism from X(A) onto x(B), when are A and B isomorphic? This problem was inspired by K-theory of C*-algebras. If μ is a UHP-algebra of type {m^p}, an orientation on x(A) and x(B), i. e., an action of the special group of μ, is introduced. Then it is obtained that if the affine isomorphism commutes with the group action then A and B are isomorphic.展开更多
It is proved that there exists a formula of first-order logic with only one non-logical symbol, a binary function symbol Ap signifying application, which uniformly defines inclusion in all BF(E)-models Some definabili...It is proved that there exists a formula of first-order logic with only one non-logical symbol, a binary function symbol Ap signifying application, which uniformly defines inclusion in all BF(E)-models Some definability results give an isomorphism between the group of bi-stable Ap -automorphisms of A and the group of permutations of A; it also implies that each BF(E)-model is determined, up to isomorphism, by the cardinal of its set of atoms.展开更多
基金supported by the Daejin University grants in 2010
文摘In this article, we prove the Hyers-Ulam-Rassias stability of the following Cauchy-Jensen functional inequality:‖f (x) + f (y) + 2f (z) + 2f (w)‖ ≤‖ 2f x + y2 + z + w ‖(0.1)This is applied to investigate isomorphisms between C*-algebras, Lie C*-algebras and JC*-algebras, and derivations on C*-algebras, Lie C*-algebras and JC*-algebras, associated with the Cauchy-Jensen functional equation 2f (x + y/2 + z + w) = f(x) + f(y) + 2f(z) + 2f(w).
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.
基金supported by the National Natural Science Foundation of China(11801555 and 11971058)the Fundamental Research Funds for the Central Universities(2020YQLX02)supported by the National Natural Science Foundation of China(11971058,11761131002 and 11671185)。
文摘Let L:=-△+V be the Schrodinger operator on R^(n)with n≥3,where V is a non-negative potential satisfying△^(-1)(V)∈L^(∞)(R^(n)).Let w be an L-harmonic function,determined by V,satisfying that there exists a positive constantδsuch that,for any x∈Rn,0<δ≤w(x)≤1.Assume that p(·):R^(n)→(0,1]is a variable exponent satisfying the globally log-Hölder continuous condition.In this article,the authors show that the mappings HL^(p)(·))(R^(n))■f■wf∈H^(p)(·)(R^(n))and HL^(p(·))(R^(n))■f■(-△)^(1/2)L^(-1/2)(f)∈H^(p(·))(R^(n))are isomorphisms between the variable Hardy spaces HL^(p(·))(R^(n)),associated with L,and the variable Hardy spaces H^(p(·))(R^(n)).
基金Supported by the National Natural Science Foundation of China.
文摘In this paper, we introduce a new approach to characterize the isomor-phisms of circulant digraphs. In terms of this method, we completely determine theisomorphic classes of circulant digraphs of degree 3. In particular, we characterizethose circulant digraphs of degree 3 which don't satisfy Adam's conjecture.
文摘In this paper, we discuss some multiplicative preservers and give some characterizations of isomorphisms or conjugate isomorphisms on β(X), where β(X) denotes the algebra of all bounded linear operators on a Banach space X.
基金supported by National Natural Science Foundation of China(Grant Nos.12061060 and 11801141)Scientific and Technological Planning Project of Yunnan Province(Grant No.202305AC160005)Scientific and Technological Innovation Team of Yunnan Province(Grant No.2020CXTD25)。
文摘We prove that a certain eventually homological isomorphism between module categories induces triangle equivalences between their singularity categories,Gorenstein defect categories and stable categories of Gorenstein projective modules.Furthermore,we show that the Auslander-Reiten conjecture and the Gorenstein symmetry conjecture can be reduced by eventually homological isomorphisms.Applying these results to arrow removal and vertex removal,we describe the Gorenstein projective modules over some non-monomial algebras and verify the Auslander-Reiten conjecture for certain algebras.
基金supported by National Natural Science Foundation of China (Grant No. 10871111)Tian Yuan Foundation of China (Grant No. 11026161)Foundation of Shanxi University
文摘Let N and M be nests on Banach spaces X and Y over the real or complex field F, respectively, with the property that if M ∈ M such that M_ =M, then M is complemented in Y. Let AlgN and AlgM be the associated nest algebras. Assume that Ф : AlgN → AlgM is a bijective map. It is proved that, if dim X = ∞ and if there is a nontrivial element in N which is complemented in X, then Ф is Lie multiplicative (i.e. Ф([A, B]) = [Ф(A), Ф(B)] for all A, B ∈ AlgN) if and only if Ф has the form Ф(A) = TAT^-1 + τ(A) for all A ∈ AlgAN or Ф(A) = -TA^*T^-1 + τ(A) for all A ∈ AlgN, where T is an invertible linear or conjugate linear operator and τ : AlgN →FI is a map with τ([A, B]) = 0 for all A, B ∈ AlgN. The Lie multiplicative maps are also characterized for the case dim X 〈 ∞.
文摘In this paper we give the following main results: (ⅰ) Let F(?) and G(?) be two free modules. Then F(?) and G(?) are semi-linearly isomorphic if and only if End F(?) and End G(?) are strictly isomorphic. (ⅱ) We give a new method to generalize the Bolla theorem in 1985 which gave a categorical description for isomorphism between End F(?) and End G(?). (ⅲ) The Wolfson theorem is a corollary of our theorem.
基金Project supported by the National Natural Science Foundation of China
文摘Let R and A be commutative rings with identity, and m and n be integers ≥3. Consider when and how an isomorphism E_m(R)E_n(A) can be lifted to an isomorphism between the corresponding Steinberg groups. It was proved that, if E_m(R) is isomorphic to E_n(A) then m=n (cf. Ref. [1]). When n≥4, every isomorphism E_n(R)E_n(A) is of the standard type, and it can be naturally and uniquely lifted to an isomorphism from St_n(R) to St_n(A) (cf. Refs. [1] and [2]). However, the case n=3 is different from that n≥4,
文摘1. Introduction Since O’Meara worked out the automorphisms of orthogonal groups Ωn(V) over fields in [4] by using well-known residual space method, many results about the isomorphisms and automorphisms of orthogonal groups over integral domains have been achieved. Refer to O’Meara, Hahn for example. B. R. McDonald, in [12], determined the automorphisms of O(V) over local rings with 2 a unit by using involutions.
基金Project supported by the National Natural Science Foundation of China.
文摘In this paper, we discuss the necessary and sufficient conditions in which there exist exceptional isomorphisms between E3(A) and E3(R) and between GL3(A) and GL3(R) for commutative rings A and R. A counterexample shows that two rings that are not isomorphic may have isomorphic tinear groups. This partly solves an open problem posed at the conference on abstract homomorphisms of algebraic groupsrs.
基金Supported by the National Natural Science Foundation of China (Grant No. 10471114)
文摘By a ball-covering B of a Banach space X, we mean that it is a collection of open balls off the origin whose union contains the sphere of the unit ball of X. The space X is said to have a ball-covering property, if it admits a ball-covering consisting of countably many balls. This paper, by constructing the equivalent norms on l~∞, shows that ball-covering property is not invariant under isomorphic mappings, though it is preserved under such mappings if X is a Gateaux differentiability space; presents that this property of X is not heritable by its closed subspaces; and the property is also not preserved under quotient mappings.
文摘In this paper, we will prove that every derivation of completely distributive subspace lattice (CDS)algebras on Banach space is automatically continuous. This is new even in the Hilbert space case. As an application of this result, we obtain that every additive derivation of nest algebras on Banach spaces is inner. We will also prove that every isomorphism between nest algebras on Banach space is automatically continuous, and in addition, is spatial.
文摘By considering the Galois action and the group action,we give the relation of two isomorphism character rings on the arbitrary field K with CharK = 0.Our results generalize Saksonov's theorem.
基金The authors would like to thank the referee for his many valuable suggestions. This work was supported by the National Natural Science Foundation of China (Grant No. 10231040).
文摘We will be mainly concerned with some important fiber spaces over Teichmuller spaces, including the Bers fiber space and Teichmuller curve, establishing an isomorphism theorem between 'punctured' Teichmuller curves and determining the biholomorphic isomorphisms of these fiber spaces.
基金This work was supported by the National Program for the Major Basic SciencesResearches of China.
文摘For integral table algebras with integral table basis T, we can consider integral R-algebra RT over a subring R of the ring of the algebraic integers. It is proved that an R-algebra isomorphism between two integral table algebras must be an integral table algebra isomorphism if it is compatible with the so-called normalizings of the integral table algebras.
文摘In this paper we propose the concept of generalized semi-Cayley graphs, which is a combination of semi-Cayley graphs and generalized Cayley graphs. We study the isomorphisms and automorphisms of generalized semi-Cayley graphs and other related properties.
文摘The following problem is discussed: If μ is an AF-algebra, A and B are two C-algebras, x(A) and x(B) are the unit balls of μ A and μ B respectively, and there is an affine isomorphism from X(A) onto x(B), when are A and B isomorphic? This problem was inspired by K-theory of C*-algebras. If μ is a UHP-algebra of type {m^p}, an orientation on x(A) and x(B), i. e., an action of the special group of μ, is introduced. Then it is obtained that if the affine isomorphism commutes with the group action then A and B are isomorphic.
基金Project partially supported by a post-doctor grant of the Chinese Academy of Sciences.
文摘It is proved that there exists a formula of first-order logic with only one non-logical symbol, a binary function symbol Ap signifying application, which uniformly defines inclusion in all BF(E)-models Some definability results give an isomorphism between the group of bi-stable Ap -automorphisms of A and the group of permutations of A; it also implies that each BF(E)-model is determined, up to isomorphism, by the cardinal of its set of atoms.