度量空间中拟对称映射与拟双曲一致域的研究

本文主要考虑度量空间中拟双曲一致域与拟对称映射之间的关系,并证明了度量空间中拟双曲一致域在拟对称映射下仍然是保持不变的.     

强John域中的Lipschitz扩张和拟双曲度量

利用拟双曲度量刻划了强John域,并且获得了强John域中拟共形映射的Hardy-Littlewood性质.     

拟度量空间中弱拟对称映射的一些特征

该文研究了弱拟对称映射在拟度量空间中的相关性质.引入了环与环性质的概念,并用环的性质来刻画了弱拟对称映射在拟度量空间中的一些特征.     

拟对称的有界度圆填充逼近

拟对称集和拟圆周集是万有Teichm(u|¨)er空间中两个常用模型.对于任一个由K-拟圆周诱导的拟对称,应用有界度圆填充的方法,构造了其近似映射,并证明了这些近似映射一致收敛于该拟对称.     

Apollonian度量与Apollonian边界条件

证明了(1)■中真子域D上的Apollonian度量αD是拟共形映射的拟不变量;(2)■中严格一致域是拟共形不变的;(3)■中的Jordan域D是拟圆当且仅当D是严格一致域,作为应用,进一步得到了Apollonian边界条件,拟共形映射和局部Lipschitz映射之间的关系。     

一类Minkowski复空间的拟距离和奇异性质

双曲虚单位对应一类Minkowski复空间并具有方向异性的特点.四维时空中特殊方向上两时空点间的减法对应类时区与类光区的几何关联,在物理中表示粒子和场的相互作用.通过定义拟(虚)距离使Minkowsk空间的时空映射和间隔不变量进行度量公理化.四维时空中不同方向的距离或度量需要用线度因子和角度因子共同刻画,其中角度因子对应模糊集合,决定了Minkowski度量空间的奇异性质.     

Apollonian度量与Apollonian边界条件

证明了(1)(-R)n中真子域D上的Apollonian度量aD是拟共形映射的拟不变量;(2)(-R)n中严格一致域是拟共形不变的;(3)(-R)2中的Jordan域D是拟圆当且仅当D是严格一致域.作为应用,进一步得到了Apollonian边界条件,拟共形映射和局部Lipschitz映射之间的关系.     

调和映射的可积拟共形延拓

本文研究了平面调和映射的可积拟共形延拓问题.利用经典的共形映射的拟共形延拓方法和调和映射的性质,获得了一些条件使得调和映射可以拟共形延拓至整个平面且其复伸缩商关于双曲度量是p次可积的,推广了解析单叶函数的相关结果.     

Gromov双曲H?lder区域的边界性质

设Ω?Rⁿ是一个满足拟双曲边界条件的Gromov双曲区域.通过使用直径型的Gehring-Hayman不等式和Bonk-Heinonen-Koskela的一致化过程,我们在此文中建立了Ω的内直径边界和Gromov边界的双边H?lder对应关系.作为应用,我们不仅可以得到拟共形映射的内直径边界连续性,也可以得到关于拟双曲度量的拟等距映射在内直径边界的连续性.     

完全分配格上的点式拟一致结构与p．q．度量

在完全分配格上建立了点式拟一致结构理论．讨论了诱导拓扑分子格中闭包，局部基，连续等性质．证明了每个拓扑分子格皆可点式拟一致化．另外借助纯距离函数与真正的远域映射族给出了［８］中ｐ．ｑ．度量的等价定义与刻画，得到了点式拟一致分子格的ｐ．ｑ．度量化定理．     

拟圆的一个充分必要条件

利用拟双曲度量研究了平面拟共形映照中的拟圆，得到了拟圆的一个充分必要条件。     

The Set of Pre-Ends and the Ideal Boundary of a Manifold without Boundary

Relations between prime pre-ends and elements of the ideal boundary of a manifold without boundary are studied. The cases of a manifold with Mazurkiewicz or Riemannian intrinsic metric and of a manifold with quasihyperbolic metric are considered.     

Quasihyperbolic boundary conditions and capacity: Hölder continuity of quasiconformal mappings

We prove that quasiconformal maps onto domains which satisfy a quasihyperbolic boundary condition are globally H?lder continuous in the internal metric. The primary improvement here over existing results along these lines is that no assumptions are made on the source domain. We reduce the problem to the verification of a capacity estimate in domains satisfing a quasihyperbolic boundary condition, which we establish using a combination of a chaining argument involving the Poincaré inequality on Whitney cubes together with Frostman's theorem. We also discuss related results where the quasihyperbolic boundary condition is slightly weakened; in this case the H?lder continuity of quasiconformal maps is replaced by uniform continuity with a modulus of continuity which we calculate explicitly. Received: June 16, 2000     

Quasihyperbolic geodesics in convex domains

We show that quasihyperbolic geodesics exist in convex domains in reflexive Banach spaces and that quasihyperbolic geodesies are quasiconvex in the norm metric in convex domains in all normed spaces.     

Gromov hyperbolicity of the and metrics

In this note it is shown that the metric is always Gromov hyperbolic, but that the metric is Gromov hyperbolic if and only if has exactly one boundary point. As a corollary we get a new proof for the fact that the quasihyperbolic metric is Gromov hyperbolic in uniform domains.

     

凸域上拟双曲测地线直径的Gehring-Hayman 恒等式

利用型函数和最大项m（σ）的几何意义研究全平面上Dirichlet级数的增长性,得到了Dirichlet级数增长性与系数、指数之间关系的四个结论,推广了以往研究增长性的相关结果.     

The Apollonian inner metric and uniform domains

In this paper we characterize uniform domains in terms of the Apollonian inner metric and the j‐metric, thus providing solutions to two open problems given in [16]. We also discuss the relationships among uniform, A‐uniform, Apollonian quasiconvex and quasi‐isotropic domains (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

The Arc Distortion in QH Inner ψ-uniform （or Convex） Domains in Real Banach Spaces

Let D and D′ be domains in real Banach spaces of dimension at least 2. The main aim of this paper is to study certain arc distortion properties in the quasihyperbolic metric defined in real Banach spaces. In particular, when D′ is a QH inner ψ-uniform domain with ψ being a slow (or a convex domain), we investigate the following: For positive constants c,h,C,M, suppose a homeomorphism f: D → D′ takes each of the 10-neargeodesics in D to (c, h)-solid in D′. Then f is C-coarsely M-Lipschitz in the quasihyperbolic metric. These are generalizations of the corresponding result obtained recently by Väisälä.     

Quasihyperbolic boundary conditions and capacity: Uniform continuity of quasiconformal mappings

We prove that quasiconformal maps onto domains which satisfy a suitable growth condition on the quasihyperbolic metric are uniformly continuous when the source domain is equipped with the internal metric. The obtained modulus of continuity and the growth assumption on the quasihyperbolic metric are shown to be essentially sharp. As a tool, we prove a new capacity estimate.     

On global integrability of BMO functions on general domains

Extending results of Staples and Smith-Stegenga, we characterize measurable subsets of a given domainD ⊃R ⁿ on which BMO(D) functions areL ^p integrable or exponentially integrable. In particular, we characterize uniform domains by the integrability of BMO functions. We also remark on the boundedness of domains satisfying a certain integrability condition for the quasihyperbolic metric.