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1.
Bergman空间上Toeplitz算子的凸性   总被引:1,自引:0,他引:1  
曹广福  孙善利  王刚 《数学学报》1995,38(6):810-816
本文讨论了Bergman空间上Toeplitz算子的凸性,证明了具有调和符号和一类连续函数符号的Toeplitz算子是凸型算子,并举例说明,存在具有连续函数符号的非凸型Toeplitz算子。  相似文献   

2.
该文引入了一类B值广义aKp鞅空间(1≤a≤p≤+∞,且a〈+∞),并获得如下主要结果:①当a〉1时,极大算子在这类空间上总是有界的。②当a≥2时,a-均方算子在这类空间上为有界的充要条件是:状态空间B是a-凸的。  相似文献   

3.
本文在算子单调性和紧性假设下研究了一类半线性算子方程Au-Tu+Cuf的可解性,其中A,T和C映实自反Banach空间X中的闭凸子集到它的对偶空间X*.我们的结果扩展或改进了Guan[1]最近宣布的全部结果.  相似文献   

4.
关于可分解算子的扰动的不变子空间(英文)   总被引:1,自引:0,他引:1  
在文献[1]中,J.Eschmeier和B.Prunaru证明了(复)Banach空间上的每个具有Bishop性质(β)和浓厚谱的有界线性算子有非平凡的不变子空间.在文献[2]中,H.Mohebi和M.Radjabalipour在减弱算子的Bishop性质(β)和加强谱的浓厚性条件的情况下得到了另外几个不变子空间定理.本文给出了一个更进一步的不变子空间定理(见定理1).  相似文献   

5.
赵焕光  洪振杰 《数学学报》2000,43(5):955-960
本文运用向量测度方法研究了Banach空问上可凹算子类与Radon-Nikodym算子类的特性,并把所得结果用于研究Banach空间的结构,给出Banach空间具有Randon-Nikodym性质的若干新特征。  相似文献   

6.
该文引入了一类B值广义αKp鞅空间(1≤a≤P≤+∞,且a<+∞),并获得如下主要结果:①当a>1时,极大算子在这类空间上总是有界的.②当a≥2时,a-均方算子在这类空间上为有界的充要条件是:状态空间B是α一凸的.  相似文献   

7.
关于广义Calderon-Zygmund算子   总被引:2,自引:1,他引:1  
本文讨论了θ(t)型和(log,θ)型Calderon-Zygmund算子在加权Hardy型空间HA^Pw上的有界性,θ(t)型Calderon-Zygmund算子在Hardy型加权块空间Bp,w上的有界性,以及广义的w-Calderon-Zygmund算子是H^p上的有界算子。  相似文献   

8.
余大海  孙顺华 《数学学报》1995,38(2):281-285
本文讨论了Toeplitz算子空间的W-闭包,我们证明了Bergman空间L^2a(D)上全体Toeplitz算子的W闭包等于B(L^2a(D)(定理1),另外,我们给出C^m(n>1)中单位球面S上的Hardy空间H^2(S)上的Toeplitz算子的一个有趣刻划(命题2)。  相似文献   

9.
引入公理化凸空间框架下的闭包算子和内部算子,分别称之为凸闭包算子和凸内部算子.结果表明,论域X上的凸结构全体不仅等价于论域X上的凸闭包算子全体,而且等价于论域X上的凸内部算子全体.  相似文献   

10.
设H为Hilbert空间.T为H上有界线性算子,对任何T的不变子空间M,称T具有Beurling-性质.本文给出了次正常算子具有Beurling-性质的充要条件.  相似文献   

11.
This paper introduces the concept of the generalized Riesz operators and the concept of the generalized West decomposition of a general operator which generalizes the definition of the West decomposition of Riesz operators, and proves that the following three statements are equivalent on a general Banach space: (a) Every generalized Riesz operator has the generalized West decomposition; (b) Every operator makes strong Stampfli theorem true; Every operator has Apostol's compact correction.  相似文献   

12.
A general Riesz merotopic space (X, ν) determines a not necessarily topological closure operator cν on X. The space (X, ν) is said to be complete if every cluster on (X, ν) is contained in an adherence grill on (X, cν). We discuss a method of obtaining a large class of completions of a given Riesz merotopic space with induced T1 closure space. As special cases we get the simple completion, which induces a simple closure space extension, and the strict completion, which induces a strict closure space extension. We show that the category of complete separated T1 Riesz merotopic spaces is epireflective in the category of separated T1 Riesz merotopic spaces, the reflection of an object being the simple completion. Similarly the category of complete clan-covered quasi-regular T1 Riesz merotopic spaces is epireflective in the category of clan-covered quasi-regular T1 Riesz merotopic spaces, the reflection of an object being the strict completion.  相似文献   

13.
Yang  Dachun 《Potential Analysis》2003,19(2):193-210
By using the discrete Calderón reproducing formulae, the author first establishes the boundedness of the Riesz-potential-type operator in homogeneous Besov and Triebel–Lizorkin spaces over spaces of homogeneous type. Then, by use of the T1 theorems for these spaces, the author proves that this operator of Riesz potential type can be used as the lifting operator of these spaces.  相似文献   

14.
设{Ei:i∈I)是侧完备Riesz空间E中的一族理想,且Ei∩Ej=θ(i,j∈I,i≠j).文章引入理想族{Ei:i∈I)直和的概念,并给出一个表示定理.文章证明了:存在一个完备的正则Hausdorff空间X使得理想族的直和Riesz同构于C(X)其充要条件是对每个i∈I存在一个紧Hausdorff空间Xi使得Ei Riesz同构于C(X).  相似文献   

15.
Let L =-? + V be a Schrdinger operator acting on L2(Rn), n ≥ 1, where V ≡ 0 is a nonnegative locally integrable function on Rn. In this article, we will intropduce weighted Hardy spaces H L(w) associated with L by means of the square function and then study their atomic decomposition theory. We will also show that the Riesz transform ?L-1/2associated with L is bounded from our new space Hp L(w) to the classical weighted Hardy space Hp(w) when n/(n +1) p 1 and w ∈ A1∩ RH(2/p)′.  相似文献   

16.
Bruce A. Watson 《Positivity》2009,13(3):543-558
In this paper we formulate and prove analogues of the Hahn-Jordan decomposition and an Andô-Douglas-Radon-Nikodým theorem in Dedekind complete Riesz spaces with a weak order unit, in the presence of a Riesz space conditional expectation operator. As a consequence we can characterize those subspaces of the Riesz space which are ranges of conditional expectation operators commuting with the given conditional expectation operators and which have a larger range space. This provides the first step towards a formulation of Markov processes on Riesz spaces.  相似文献   

17.
本文研究了紧致齐性空间上的Riesz位势算子与Bessel位势算子,Riesz变换与Bessel变换,给出了上述算子对应的核函数的具体构造并证明了Riesz变换与Bessel变换作为奇异积分算子的H ̄p有界性,p>0。  相似文献   

18.
In this paper, we extend the Moreau (Riesz) decomposition theorem from Hilbert spaces to Banach spaces. Criteria for a closed subspace to be (strongly) orthogonally complemented in a Banach space are given. We prove that every closed subspace of a Banach space X with dim X ≥ 3 (dim X ≤ 2) is strongly orthognally complemented if and only if the Banach space X is isometric to a Hilbert space (resp. strictly convex), which is complementary to the well-known result saying that every closed subspace of a Banach space X is topologically complemented if and only if the Banach space X is isomorphic to a Hilbert space.  相似文献   

19.
Abramovich  Y. A.  Chen  Z. L.  Wickstead  A. W. 《Positivity》1997,1(1):75-96
The main results obtained are:– A Dedekind complete Banach lattice Y has a Fatou norm if and only if, for any Banach lattice X, the regular-norm unit ball Ur = {T Lr(X,Y): ||T||r 1} is closed in the strong operator topology on the space of all regular operators, Lr(X,Y).– A Dedekind complete Banach lattice Y has a norm which is both Fatou and Levi if and only if, for any Banach lattice X, the regular-norm unit ball Ur is closed in the strong operator topology on the space of all bounded operators, L(X,Y).– A Banach lattice Y has a Fatou–Levi norm if and only if for every L-space X the space L(X,Y) is a Banach lattice under the operator norm.– A Banach lattice Y is isometrically order isomorphic to C(S) with the supremum norm, for some Stonean space S, if and only if, for every Banach lattice X, L(X,Y) is a Banach lattice under the operator norm.Several examples demonstrating that the hypotheses may not be removed, as well as some applications of the results obtained to the spaces of operators are also given. For instance:– If X = Lp() and Y = Lq(), where 1 < p,q < , then Lr(X,Y) is a first category subset of L(X,Y).  相似文献   

20.
熊洪允  荣喜民 《数学学报》1998,41(3):455-458
设{Ei:i∈I}是一族ArchmideanRiesz空间.记Πi∈IEi为Riesz乘积空间.此文的主要结论是:存在一个完全正则Housdorf空间X使得Πi∈IEiRiesz同构于C(X)的充分必要条件是对每一个i∈I存在一个完全正则Housdorf空间Xi使得EiRiesz同构于C(Xi).  相似文献   

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