保持Jordan多重η-*-积的非线性映射

设η≠-1是一个非零复数,Φ是两个von Neumann代数间的不必为线性的双射(其中一个代数无中心交换投影),如果满足Φ(I)=I,并且保持Jordan多重η-*-积.则当η不是实数时,Φ是一个线性*-同构;当η是实数时,Φ是一个线性*-同构和一个共轭线性*-同构的和.     

L*-逆半群的结构

定义了L*-逆半群,并引入了半群左圈积的概念.证明了半群S是一个L*-逆半群,当且仅当S是一个型A半群Γ和一个左正则带B连同结构映射ψ的左圈积B( )ψΓ.这一结果的一个直接推论是关于左逆半群结构的著名Yamada定理.利用半群的左圈积,给出了一个非平凡的L*-逆半群的例子.     

Noether环上的＊-模、余＊-模及cotilting模

设R为Noether环,讨论了R上*-模的投射性和内射性,引进与*-模相对偶的概念:余*-模,给出了R上余*-模的特征性质,最后用余*-模给出了R上cotilting模的刻划.     

因子von Neumann代数上的k-Jordan*映射

设A和B是两个因子yon Neumann代数,k是n次单位根.证明了任意的A,B∈A,非线性双射Φ:A→B满足Φ(k(AB+BA*))=k(Φ(A)Φ(B)+Φ(B)Φ(A)*)当且仅当Φ是*-环同构.     

因子von Neumann代数上的κ-Jordan*映射

设A和B是两个因子von Neumann代数,k是n次单位根.证明了任意的A,B∈A,非线性双射Φ:A→B满足Φ(k(AB+BA~*))=k(Φ(A)Φ(B)+Φ(B)Φ(A)~*)当且仅当Φ是*-环同构.     

W~*-三元算子环的摄动

本文证明了:如果两个W~*-三元算子环V和W的cb距离d_(cb)(V,W)很小的时候,其连接冯·诺依曼代数之间的距离也很小.还证明了:和内射的W~*-三元算子环靠的很近的W~*-三元算子环也是内射的.对具有r性质和McDuff性质的W~*-三元算子环,类似的结论也成立.     

素＊-环上非线性保XY-ξYX~＊积

设M是包含非平凡投影P的单位素*-环.证明了非线性双射φ:M→M对所有A,B∈M,满足φ(AB-ξBA*)=φ(A)φ(B)—ξφ(B)φ(A)*.若ξ=1,则φ是线性或共轭线性的*-同构;若ξ≠1,则φ是*-环同构,且对所有A∈M,有φ(ξA)=ξφ(A).     

具有连续对合运算的实Banach*代数的Jordan结构

本文讨论了实Banach*代数的Jordan结构．主要结果:第一部分指出映射到 *-半单实Banach*代数上的Jordan*同态是连续的,且其核空间是闭*理想;由映射到交换实Banach*代数上的Jordan*同态诱导的因子代数也是交换的．第二部分介绍了两个不同的锥,并讨论了他们间的关系．另外,我们得到了关于实Banach*代数*- 根基的一个新的刻画．本文是Satish Shirali的工作的实化．     

零可换环的一些性质

本文刻画了零可换环的一些性质,同时将交换环上的一些结果推广到零可换环上.对于零可换环R证明了(1)R是强正则环当且仅当R中每个为零化子的本质左理想是左GP-内射模或R中存在一个极大左理想K,使得K中每个元素的零化子是左GP-内射模;(2)R是GPP-环当且仅当R是拟π-正则的GPF-环.     

零可换环的一些性质

本文刻画了零可换环的一些性质,同时将交换环上的一些结果推广到零可换环上.对于零可换环R 证明了: (1)R是强正则环当且仅当R中每个为零化子的本质左理想是左GP.内射模或R中存在一个极大左理想K,使得K中每个元索的零化子是左GP-内射模; (2)R是GPP-环当且仅当R是拟π-正则的GPF-环.     

Non-Negative Integer Matrix Representations of a $\mathbb{Z}_{+}$-Ring

The $\mathbb{Z}_{+}$-ring is an important invariant in the theory of tensor category. In this paper, by using matrix method, we describe all irreducible $\mathbb{Z}_{+}$-modules over a $\mathbb{Z}_{+}$-ring $\mathcal{A}$, where $\mathcal{A}$ is a commutative ring with a $\mathbb{Z}_{+}$-basis{$1$, $x$, $y$, $xy$} and relations: $$ x^{2}=1,\;\;\;\;\; y^{2}=1+x+xy.$$We prove that when the rank of $\mathbb{Z}_{+}$-module $n\geq5$, there does not exist irreducible $\mathbb{Z}_{+}$-modules and when the rank $n\leq4$, there exists finite inequivalent irreducible $\mathbb{Z}_{+}$-modules, the number of which is respectively 1, 3, 3, 2 when the rank runs from 1 to 4.     

具有对称自同态的环及其扩张

Let R be a ring with an endomorphism α and an α-derivation δ. We introduce the notions of symmetric α-rings and weak symmetric α-rings which are generalizations of symmetric rings and weak symmetric rings, respectively, discuss the relations between symmetricα-rings and related rings and investigate their extensions. We prove that if R is a reduced ring and α(1) = 1, then R is a symmetric α-ring if and only if R[x]/(x n) is a symmetric ˉα-ring for any positive integer n. Moreover, it is proven that if R is a right Ore ring, α an automorphism of R and Q(R) the classical right quotient ring of R, then R is a symmetric α-ring if and only if Q(R) is a symmetric ˉα-ring. Among others we also show that if a ring R is weakly 2-primal and(α, δ)-compatible, then R is a weak symmetric α-ring if and only if the Ore extension R[x; α, δ] of R is a weak symmetric ˉα-ring.     

关于核型$C^{*}$代数单调积的注记

Given two nuclear C^＊-algebras A1 and A2 with states φ1 and φ2, we show that the monotone product C^＊-algebra A1 △→ A2 is still nuclear. Furthermore, if both the states φ1 and φ2 are faithful, then the monotone product ,A1 △→ A2 is nuclear if and only if the C^＊-algebras ,A1 and A2 both are nuclear.     

The range of a ring homomorphism from a commutative -algebra

We prove that if a commutative semi-simple Banach algebra is the range of a ring homomorphism from a commutative -algebra, then is -equivalent, i.e. there are a commutative -algebra and a bicontinuous algebra isomorphism between and . In particular, it is shown that the group algebras , and the disc algebra are not ring homomorphic images of -algebras.

     

具有对合运算的$n$-clean环

A *-ring is called *-clean if every element of the ring can be written as the sum of a projection and a unit. For an integer n ≥ 1, we call a *-ring R n-*-clean if for any a ∈ R,a = p + u1 + ··· + unwhere p is a projection and ui are units for all i. Basic properties of n-*-clean rings are considered, and a number of illustrative examples of 2-*-clean rings which are not *-clean are provided. In addition, extension properties of n-*-clean rings are discussed.     

**-Haagerup Property for C*-Algebras

Extending the notion of Haagerup property for finite von Neumann algebras to the general von Neumann algebras, the authors define and study the $(**)$-Haagerup property for $C^{*}$-algebras in this paper. They first give an answer to Suzuki''s question (2013), and then obtain several results of $(**)$-Haagerup property parallel to those of Haagerup property for $C^{*}$-algebras. It is proved that a nuclear unital $C^{*}$-algebra with a faithful tracial state always has the $(**)$-Haagerup property. Some heredity results concerning the $(**)$-Haagerup property are also proved.     

Indecomposable Modules and Gelfand Rings

It is proved that a commutative ring is clean if and only if it is Gelfand with a totally disconnected maximal spectrum. It is shown that each indecomposable module over a commutative ring R satisfies a finite condition if and only if R _P is an Artinian valuation ring for each maximal prime ideal P. Commutative rings for which each indecomposable module has a local endomorphism ring are studied. These rings are clean and elementary divisor rings. It is shown that each commutative ring R with a Hausdorff and totally disconnected maximal spectrum is local-global. Moreover, if R is arithmetic, then R is an elementary divisor ring.     

Linear maps preserving ideals of C-algebras

We show that every unital linear bijection which preserves the maximal left ideals from a semi-simple Banach algebra onto a C-algebra of real rank zero is a Jordan isomorphism. Furthermore, every unital self-adjoint linear bijection on a countably decomposable factor von Neumann algebra is maximal left ideal preserving if and only if it is a *-automorphism.

     

Reduction of Matrices over Bezout Rings of Stable Rank not Higher than 2

We prove that a commutative Bezout ring is an Hermitian ring if and only if it is a Bezout ring of stable rank 2. It is shown that a noncommutative Bezout ring of stable rank 1 is an Hermitian ring. This implies that a noncommutative semilocal Bezout ring is an Hermitian ring. We prove that the Bezout domain of stable rank 1 with two-element group of units is a ring of elementary divisors if and only if it is a duo-domain.     

The Ideal Intersection Property for Groupoid Graded Rings

We show that, if a groupoid graded ring has a grading satisfying a certain nondegeneracy property, then the commutant of the center of the principal component of the ring has the ideal intersection property, that is it intersects nontrivially every nonzero ideal of the ring. Furthermore, we show that for skew groupoid algebras with commutative principal component, the principal component is maximal commutative if and only if it has the ideal intersection property.