关于局部双全纯映射的推广的Roper-Suffridge算子

§ 1.　Introduction　　LetUbetheunitdiskinCandBnbetheunitballinCn.In 1 995 ,RoperandSuffridgeintroducedanextensionoperator.ThisoperatorisdefinedforanormalizedlocallybiholomorphicfunctionfonUbyΦn(f) (z) =F(z) =(f(z1 ) ,f′(z1 )z′) ,z =(z1 ,z′)∈Bn,(1 .1 )wherez1 ∈U ,z′=(z2 ,… ,zn)∈Cn- 1 ,andthebranchofthesquarerootischosensuchthatf′(0 ) =1 .TheRoper Suffridgeextensionoperatorhasthefollowingimportantproperties:(a)IffisanormalizedconvexfunctiononU ,thenFisanormalizedconvexmappingon…     

一致连续映射的两个扩张定理

把文[1],[2]中的两个定理进行了拓广和改进,给出两个一致连续映射的扩张定理:(i)任一集合A到一个完备度量空间的一致连续映射可一致连续扩张到A珡上.(ii)任一闭集A到Rn的一致连续映射可一致连续扩张到A与任一紧集的并.     

Extension of an abstract attainability problem with the use of the stone representation space

We consider an attainability problem in a complete metric space on values of an objective operator h. We assume that the latter admits a uniform approximation by mappings which are tier with respect to a given measurable space with an algebra of sets. Let asymptotic-type constraints be defined as a nonempty family of sets in this measurable space. We treat ultrafilters of the measurable space as generalized elements; we equip this space of ultrafilters with a topology of a zero-dimensional compact (the Stone representation space). On this base we construct a correct extension of the initial problem, realizing the set of attraction in the form of a continuous image of the compact of feasible generalized elements. Generalizing the objective operator, we use the limit with respect to ultrafilters of the measurable space. This provides the continuity of the generalized version of h understood as a mapping of the zero-dimensional compact into the topological space metrizable with a total metric.     

B~n上推广的Roper-Suffridge算子的性质

讨论改进后的Roper-Suffridge延拓算子保持双全纯映照子族的性质.借助双全纯映照子族的解析特征及其偏差结论,得到改进后的Roper-Suffridge延拓算子在一定条件下保持α次殆β型螺形映照、α次β型螺形映照、强β型螺形映照的性质,从而得到改进后的算子在一定条件下保持α次殆星形性、α次星形性和强星形性.所得结论为在多复变数空间中构造这些双全纯映照提供了一种新的途径.     

非满等距映射的线性延拓

主要研究实赋范空间E和F的单位球面S_1(E)和S_1(F)之间的等距映射的线性延拓问题．得到：若等距映射V_0：S_1(E)→S_1(F)满足一定条件,则V_0可延拓为全空间E上的线性等距映射V：E→F,这是我们首次在非满的情况下考虑Tingley问题．     

重单值扩张算子的谱结构与拟相似

本文证明了,若T是重单值扩张算子,则若T1是重单值扩张（C）算子,T2是任一有界线性算子,T1与T2拟相似,则σe（T1）＝σk（T1）σk（T2）＝σe（T2）     

二维严格凸赋范空间单位球面间等距映射的线性延拓

主要研究二维严格凸实赋范空间E和F的单位球面S_1(E)和S_1(F)之间的等距映射的线性延拓问题.利用二维严格凸赋范空间单位球面的性质得到:若等距映射V_0:S_1(E)→S_1(F)满足一定条件,则V_0可延拓为全空间E上的线性等距映射V:E→F.     

可拓概率空间讨论

本文提出了Ⅰ型和Ⅱ型可拓概率空间两个概念,并讨论了它们的一般性质     

COINCIDENCE THEOREMS INVOLVING COMPOSITES OF ACYCLIC MAPPINGS AND APPLICATIONS

Some new coincidence theorems involving a newclass of set-valued mappings containing composites of acyclic mappings definedon a contractible space are proved. As applications, some existence theoremsof maximal elements and solutions of abstract variational inequalities, andbest approximation theorems are proved. These theorems improve and generalizea number of known results in recent literature.     

On a generalized Mazur-Ulam question: Extension of isometries between unit spheres of Banach spaces

We call a Banach space X admitting the Mazur-Ulam property (MUP) provided that for any Banach space Y, if f is an onto isometry between the two unit spheres of X and Y, then it is the restriction of a linear isometry between the two spaces. A generalized Mazur-Ulam question is whether every Banach space admits the MUP. In this paper, we show first that the question has an affirmative answer for a general class of Banach spaces, namely, somewhere-flat spaces. As their immediate consequences, we obtain on the one hand that the question has an approximately positive answer: Given ε>0, every Banach space X admits a (1+ε)-equivalent norm such that X has the MUP; on the other hand, polyhedral spaces, CL-spaces admitting a smooth point (in particular, separable CL-spaces) have the MUP.     

柏龙树(THE PERRON TREE)定理的推广与应用

将平面上的柏龙树(the Perron Tree)定理推广了k维欧氏空间,由此推广了Fefferman定理.     

A Theorem for Generalized Extension ofOperators and Some Applications

In this note it is shown that every bounded linear operator T Э B(Y,Z)defined on a closed subspace Y of a Banach space X admits a generalized extension T Э B(X, V). Some examples of the applications are given; especially, a characterization of H.I. spaces is obtained.     

The closure of planar diffeomorphisms in Sobolev spaces

We characterize the (sequentially) weak and strong closure of planar diffeomorphisms in the Sobolev topology and we show that they always coincide. We also provide some sufficient condition for a planar map to be approximable by diffeomorphisms in terms of the connectedness of its counter-images, in the spirit of Young's characterisation of monotone functions. We finally show that the closure of diffeomorphisms in the Sobolev topology is strictly contained in the class INV introduced by Müller and Spector.     

锥线性算子的延拓定理

建立了一种锥分离定理,据此证明了锥线性算子的延拓定理,作为应用,给出了正线性算子的延拓定理。     

Operators Which Do Not Have the Single Valued Extension Property

In this paper we shall consider the relationships between a local version of the single valued extension property of a bounded operator T  L(X) on a Banach space X and some quantities associated with T which play an important role in Fredholm theory. In particular, we shall consider some conditions for which T does not have the single valued extension property at a point λ_o  C.     

严格集压缩映射和凝聚映射的延拓定理及应用(英文)

应用著名的Dugundji延拓定理和Urysohn引理,将Hilbert空间E中有界闭凸集D上的k-集压缩映射和聚映射延拓到全空间,并给出了其在拓扑度计算方面的应用.     

关于正双线性算子扩张的注记

研究了定义在Riesz空间Cartesian乘积的序理想上的正双线性算子的扩张问题,得到了该类算子关于向量格运算的表达.     

Reflected Dirichlet Forms and the Uniqueness of Silverstein's Extension

Reflected Dirichlet space for quasi-regular Dirichlet forms is presented in this paper. We show the closedness of the (active) reflected Dirichlet forms without using the first definition of reflected Dirichlet space by Silverstein and the characterization by Chen. As an application of the closedness, the closability of distorted forms are discussed. We also show the maximality of (active) reflected Dirichlet space in the class of Silverstein's extensions and consider the uniqueness problem. Only the techniques of the transfer method and the change of underlying measures are used.     

$(\omega_1)$性质与单值延拓性质

In this note we study the property（ω1）,a variant of Weyl＇s theorem by means of the single valued extension property,and establish for a bounded linear operator defined on a Banach space the necessary and sufficient condition for which property（ω1） holds.As a consequence of the main result,the stability of property（ω1） is discussed.     

论向量积在高维空间的推广

探讨了3维欧氏空间的向量积在高维空间推广的可能性.在三条假设下推导出高维空间中的向量积所应具备的若干性质,证明了在某些意义下向量积仅存在于R3,并举例说明R7与R3中向量积不同的根源.