The Proof of Inseparable Prime AW^＊—Algebras Being Primitive C^＊—Algebras

The relation between the inseparable prime C^*-algebras and primitive C^*-algebras is studied,and we prove that prime AW^*-algebras are all primitive C^*-algebras.     

Lifting Unitary Elements with Application to Approximately Inner Automorphisms

Let A be a separable unital nuclear simple C＊-algebra with torsion K0 （A）, free K1 （A） and with the UCT. Let T ： A→M（K）/K be a unital homomorphism. We prove that every unitary element in the commutant of T（A） is an exponent, thus it is liftable. We also prove that each automorphism α on E with α ∈ Aut0（A） is approximately inner, where E is a unital essential extension of A by K and α is the automorphism on A induced by α.     

C_2及 C~*-代数上的初等算子

Bojan Magalna 和 Sen-yen Shaw 分别在[4][5]中讨论了导算子δ_(AB):X→AX—XB 和初等算子 τ_(AB):X→AXB 限制在 C_2上的自伴性及正规、次正规性,并指出所得结果对一般初等算子不成立.本文首先给出一般初等算子为自伴算子的充要条件,进而得出τ_(AB)为 C_p(1≤p≤+∞)类算子的充要条件,并将结果推广到了 C~*-代数上.     

Rational time-frequency multi-window subspace Gabor frames and their Gabor duals

This paper addresses the theory of multi-window subspace Gabor frame with rational time-frequency parameter products.With the help of a suitable Zak transform matrix,we characterize multi-window subspace Gabor frames,Riesz bases,orthonormal bases and the uniqueness of Gabor duals of type I and type II.Using these characterizations we obtain a class of multi-window subspace Gabor frames,Riesz bases,orthonormal bases,and at the same time we derive an explicit expression of their Gabor duals of type I and type II.As an application of the above results,we obtain characterizations of multi-window Gabor frames,Riesz bases and orthonormal bases for L2(R),and derive a parametric expression of Gabor duals for multi-window Gabor frames in L2(R).     

C（X）×＿αZ＿n的理想构造

本文讨论以叉积Ｃ（Ｘ）×＿αＺ＿ｎ的理想构造，这里Ｘ是紧Ｈａｕｓｄｏｒｆｆ空间，α是Ｘ的一个同胚，并且周期为ｎ，即α￣ｎ＝ｉｄ（ｎ是固定的正整数）。我们刻划了Ｃ（Ｘ）×＿αＺ＿ｎ上所有的纯态的西等价类，及其所有的本原理想，由此给出它的任何闭双侧＊理想的特征。     

Kaplansky Density and Kadison Transitivity Theorems for Irreducible Representations of Real C＊-Algebras

We prove analogs of the Kaplansky Density Theorem and the Kadison Transitivity Theorem for irreducible representations of a real C＊-algebra on a real Hilbert space. Specifically, if a C＊-algebra is acting irreducibly on a real Hilbert space, then the Hilbert space has either a real, complex, or quaternionic structure with respect to which the density and transitivity theorems hold.     

Robustness and Iterative Reconstruction of $g$-Fusion Frames in Hilbert Spaces

Regarding the application of the fusion frames and generalization of them in data proceeding, their iterative is of particular importance when one of their members is deleted. In this note, a method for reconstruction of generalized fusion frames and error operator with its upper bound are presented. Also, the approximation operator for these frames will be introduced and we study some results about them.     

有限维代数扩张的同构与维数群

对于有限维C＊-代数A，证明了其本质扩张的同构与酉等价是一致的，由此证明了扩张群Ext（A）中的等价类是区分该类扩张代数的完全不变量，并利用Bratteli图计算出它们的维数群．     

Unified Approach to the Expression for the Moore-Penrose Inverse of a- xy

Let .4 be an unital C＊-algebra, a,x and y are elements in .A. In this paper, we present a method how to calculate the Moore-Penrose inverse of a - xy＊ and investigate the expression for some new special cases of （a - xy）.     

广义Frame与广义Frame的商

本文将frame、frame同态、商frame与核的概念在范畴意义下作推广,并且证明Frame范畴是广义Frame范畴的反射子范畴.进而讨论了一个广义frame A的商与A上核函子之间的关系.特别地,我们证明了A上全部核函子所构成的范畴N(A)是一个广义frame.     

On frames for countably generated Hilbert -modules

Let be a countably generated Hilbert -module over a -algebra We prove that a sequence is a standard frame for if and only if the sum converges in norm for every and if there are constants such that for every We also prove that surjective adjointable operators preserve standard frames. A class of frames for countably generated Hilbert -modules over the -algebra of all compact operators on some Hilbert space is discussed.

     

Hilbert C*模上的Gabor酉系统

本文引入了Hilbert C*-模上的Gabor酉系统的概念,研究了它的基本性质,证明了膨胀定理,并给出某个酉系统的两个正规框架向量不相交的等价条件.     

On the bounded part of a Hilbert module over a locally C *-algebra

We will show that the bounded part of the locally C^*-algebra of all adjointable operators on the Hilbert A-module E is isomorphic to the C^*-algebra L _b(A)(b(E)) of all adjointable operators on the Hilbert b(A)-module b(E). This revised version was published online in June 2006 with corrections to the Cover Date.     

带有Radon-Nikodym导数的算子值自由Fisher信息量

本文研究了带有Radon-Nikodym导数的算子值自由Fisher信息量.利用模框架理论,得到了一个半圆元和一个子代数之间的合并自由关系,推广了D.Voiculescu等人的工作.     

W~*-代数中的C~*-端点

本文讨论Ｗ＊－代数Ａ中闭单位球Ａ１的Ｃ＊－端点问题．主要结果是：是一个投影｝；一个对称元｝；其中，Ａ～Ｓ１和Ａ～Ｐ１分别表Ａ１中自伴元全体所构成的集合和Ａ１中正元全体所构成的集合．     

Some Results on Inner Quasidiagonal C*-algebras

In the current article, we prove the crossed product C^*-algebra by a Rokhlin action of finite group on a strongly quasidiagonal C^*-algebra is strongly quasidiagonal again. We also show that a just-infinite C^*-algebra is quasidiagonal if and only if it is inner quasidiagonal. Finally, we compute the topological free entropy dimension in just-infinite C^*-algebras.     

可补Hilbert C*-模及其有界模映射

给出了可补Hilbert C^*-模一系列等价刻画，获得了一类有界模映射的分解定理。     

线性Ce^＊—半范数的次可乘性

证明了具有单位元的*-代数上的任何线性Ce^*-半范数（或具有自伴核的线性Ce0^*-半范数）一定是C^*-半范数。     

Quasidiagonal representations of nilpotent groups

We show that every unitary representation of a discrete solvable virtually nilpotent group G is quasidiagonal. Roughly speaking, this says that every unitary representation of G   approximately decomposes as a direct sum of finite dimensional approximate representations. In operator algebraic terms we show that C^?(G)$C^{?}(G)$ is strongly quasidiagonal.     

关于一个次可乘定理

本文证明了次可乘定理：设A是一个*代数,A上范数||.||使得（A,||.||）成为完备的赋范线性空间,而且,（I）对于X∈A,||x*x||||x||2;（II）对于正规元x∈A,||x*x||=||x||2,则（A,||.||）是C*-代数．同时,也给出了其对应的C*-等价定理．