Let R be a unital *-ring with the unit I. Assume that R contains a symmetric idempotent P which satisfies ARP= 0 implies A = 0 and AR(I - P) = 0 implies A = 0. In this paper, it is shown that a surjective map Ф:...Let R be a unital *-ring with the unit I. Assume that R contains a symmetric idempotent P which satisfies ARP= 0 implies A = 0 and AR(I - P) = 0 implies A = 0. In this paper, it is shown that a surjective map Ф: R →R is strong skew commutativity preserving (that is, satisfies Ф(A)Ф(B) - Ф(B)Ф(A)* : AB- BA* for all A, B ∈R) if and only if there exist a map f : R → ZSz(R) and an element Z ∈ ZS(R) with Z^2 =I such that Ф(A) =ZA + f(A) for all A ∈ R, where ZS(R) is the symmetric center of R. As applications, the strong skew commutativity preserving maps on unital prime *-rings and von Neumann algebras with no central summands of type I1 are characterized.展开更多
为了促进交换性的发展,根据半质环及半单环的相关资料,扩展了文献[1-2]的结论,得出了环的两个交换性定理:定理1:设R为一个半质环,若对▽x1,x2,…,xn∈R,有依赖于x1,x2的整系数多项式p(t)使得[…[[x1-x12p(x1),x2],x3],…,xn]∈Z(R),则R...为了促进交换性的发展,根据半质环及半单环的相关资料,扩展了文献[1-2]的结论,得出了环的两个交换性定理:定理1:设R为一个半质环,若对▽x1,x2,…,xn∈R,有依赖于x1,x2的整系数多项式p(t)使得[…[[x1-x12p(x1),x2],x3],…,xn]∈Z(R),则R为交换环。定理2:设R为一个kothe半单纯环,若对▽a,b,x2,…,xn∈R都有一正整数K=K(a,b),一含有x2和n=n(a,b)(≥K)个y的字fx(x,y)及一整系数多项式φx(x,y)使得[…[[∑ki=0αi bi abk-i-fx(a,b)φx(a,b),x2],x3],…,xn]∈Z(R)其中|∑ki=0αi|=1,则R为交换环.展开更多
Let R be a prime ring, L a non-central Lie ideal of R and g a non-zero generalized derivation of R. If g acts as a Jordan homomorphism on L, then either g(x) = x for all x ∈ R, or char(R) = 2, R satisfies the sta...Let R be a prime ring, L a non-central Lie ideal of R and g a non-zero generalized derivation of R. If g acts as a Jordan homomorphism on L, then either g(x) = x for all x ∈ R, or char(R) = 2, R satisfies the standard identity s4(x1, x2, x3, x4), L is commutative and u2 ∈ Z(R), for any u C L. We also examine some consequences of this result related to generalized derivations which act as Jordan homomorphisms on the set [I, I], where I is a non-zero right ideal of R.展开更多
A classical problem in ring theory is to study conditions under which a ring is forced to become commutative. Stimulated from Jacobson's famous result, several tech- niques are developed to achieve this goal. In the ...A classical problem in ring theory is to study conditions under which a ring is forced to become commutative. Stimulated from Jacobson's famous result, several tech- niques are developed to achieve this goal. In the present note, we use a pair of rings, which are the ingredients of a Morita context, and obtain that if one of the ring is prime with the generalized (α β)-derivations that satisfy certain conditions on the trace ideal of the ring, which by default is a Lie ideal, and the other ring is reduced, then the trace ideal of the reduced ring is contained in the center of the ring. As an outcome, in case of a semi-projective Morita context, the reduced ring becomes commutative.展开更多
A commutative ring R is called extending if every ideal is essential in a direct summand of RR. The following results are proved: (1) C(X) is an extending ring if and only if X is extremely disconnected; (2) S...A commutative ring R is called extending if every ideal is essential in a direct summand of RR. The following results are proved: (1) C(X) is an extending ring if and only if X is extremely disconnected; (2) Spec(R) is extremely disconnected and R is semiprime if and only if R is a nonsingular extending ring; (3) Spec(R) is extremely disconnected if and only if R/N(R) is an extending ring, where N(R) consists of all nilpotent elements of R. As an application, it is also shown that any Gelfand nonsingular extending ring is clean.展开更多
Let R be a prime ring of characteristic different from two with the second involution∗andαan automorphism of R.An additive mapping F of R is called a generalized(α,α)-derivation on R if there exists an(α,α)-deriv...Let R be a prime ring of characteristic different from two with the second involution∗andαan automorphism of R.An additive mapping F of R is called a generalized(α,α)-derivation on R if there exists an(α,α)-derivation d of R such that F(xy)=F(x)α(y)+α(x)d(y)holds for all x,y∈R.The paper deals with the study of some commutativity criteria for prime rings with involution.Precisely,we describe the structure of R admitting a generalized(α,α)-derivation F satisfying any one of the following properties:(i)F(xx∗)−α(xx∗)∈Z(R),(ii)F(xx∗)+α(xx∗)∈Z(R),(iii)F(x)F(x∗)−α(xx∗)∈Z(R),(iv)F(x)F(x∗)+α(xx∗)∈Z(R),(v)F(xx∗)−F(x)F(x∗)∈Z(R),(vi)F(xx∗)−F(x∗)F(x)=0 for all x∈R.Also,some examples are given to demonstrate that the restriction of the various results is not superfluous.In fact,our results unify and extend several well known theorems in literature.展开更多
基金Supported by Natural Science Foundation of Shandong Province,China(Grant No.ZR2015Item PA010)National Natural Science Foundation of China(Grant Nos.11526123 and 11401273)
文摘Let R be a unital *-ring with the unit I. Assume that R contains a symmetric idempotent P which satisfies ARP= 0 implies A = 0 and AR(I - P) = 0 implies A = 0. In this paper, it is shown that a surjective map Ф: R →R is strong skew commutativity preserving (that is, satisfies Ф(A)Ф(B) - Ф(B)Ф(A)* : AB- BA* for all A, B ∈R) if and only if there exist a map f : R → ZSz(R) and an element Z ∈ ZS(R) with Z^2 =I such that Ф(A) =ZA + f(A) for all A ∈ R, where ZS(R) is the symmetric center of R. As applications, the strong skew commutativity preserving maps on unital prime *-rings and von Neumann algebras with no central summands of type I1 are characterized.
文摘为了促进交换性的发展,根据半质环及半单环的相关资料,扩展了文献[1-2]的结论,得出了环的两个交换性定理:定理1:设R为一个半质环,若对▽x1,x2,…,xn∈R,有依赖于x1,x2的整系数多项式p(t)使得[…[[x1-x12p(x1),x2],x3],…,xn]∈Z(R),则R为交换环。定理2:设R为一个kothe半单纯环,若对▽a,b,x2,…,xn∈R都有一正整数K=K(a,b),一含有x2和n=n(a,b)(≥K)个y的字fx(x,y)及一整系数多项式φx(x,y)使得[…[[∑ki=0αi bi abk-i-fx(a,b)φx(a,b),x2],x3],…,xn]∈Z(R)其中|∑ki=0αi|=1,则R为交换环.
文摘Let R be a prime ring, L a non-central Lie ideal of R and g a non-zero generalized derivation of R. If g acts as a Jordan homomorphism on L, then either g(x) = x for all x ∈ R, or char(R) = 2, R satisfies the standard identity s4(x1, x2, x3, x4), L is commutative and u2 ∈ Z(R), for any u C L. We also examine some consequences of this result related to generalized derivations which act as Jordan homomorphisms on the set [I, I], where I is a non-zero right ideal of R.
文摘A classical problem in ring theory is to study conditions under which a ring is forced to become commutative. Stimulated from Jacobson's famous result, several tech- niques are developed to achieve this goal. In the present note, we use a pair of rings, which are the ingredients of a Morita context, and obtain that if one of the ring is prime with the generalized (α β)-derivations that satisfy certain conditions on the trace ideal of the ring, which by default is a Lie ideal, and the other ring is reduced, then the trace ideal of the reduced ring is contained in the center of the ring. As an outcome, in case of a semi-projective Morita context, the reduced ring becomes commutative.
基金supported by National Natural Science Foundation of China (10671122)supported by Collegial Natural Science Research Program of Education Department of Jiangsu Province (07KJD110179)
文摘A commutative ring R is called extending if every ideal is essential in a direct summand of RR. The following results are proved: (1) C(X) is an extending ring if and only if X is extremely disconnected; (2) Spec(R) is extremely disconnected and R is semiprime if and only if R is a nonsingular extending ring; (3) Spec(R) is extremely disconnected if and only if R/N(R) is an extending ring, where N(R) consists of all nilpotent elements of R. As an application, it is also shown that any Gelfand nonsingular extending ring is clean.
基金Supported by the University Science Research Project of Anhui Province(Grant Nos.KJ2020A0711,KJ2020ZD74,KJ2021A1096)the Natural Science Foundation of Anhui Province(Grant No.1908085MA03)。
文摘Let R be a prime ring of characteristic different from two with the second involution∗andαan automorphism of R.An additive mapping F of R is called a generalized(α,α)-derivation on R if there exists an(α,α)-derivation d of R such that F(xy)=F(x)α(y)+α(x)d(y)holds for all x,y∈R.The paper deals with the study of some commutativity criteria for prime rings with involution.Precisely,we describe the structure of R admitting a generalized(α,α)-derivation F satisfying any one of the following properties:(i)F(xx∗)−α(xx∗)∈Z(R),(ii)F(xx∗)+α(xx∗)∈Z(R),(iii)F(x)F(x∗)−α(xx∗)∈Z(R),(iv)F(x)F(x∗)+α(xx∗)∈Z(R),(v)F(xx∗)−F(x)F(x∗)∈Z(R),(vi)F(xx∗)−F(x∗)F(x)=0 for all x∈R.Also,some examples are given to demonstrate that the restriction of the various results is not superfluous.In fact,our results unify and extend several well known theorems in literature.