共查询到20条相似文献,搜索用时 46 毫秒
1.
Warsaw圈上映射的等度连续性 总被引:4,自引:0,他引:4
设W是Warsaw圈:f:W→W是连续映射,本证明f是等度连续映射的充分必要条件是下列两个条件之一成立:(1)F(f)是一个单点集并且F(f^2)=∩^∞n=1f^n(W);(2)F(f)=∩^∞n=1f^n(W)。 相似文献
2.
在扩大模型下,应用单子理论给出了拓扑等度连续和均匀连续的非标准刻画,并应用均匀连续的非标准特征证明了网收敛与均匀连续之间的关系,最后应用拓扑等度连续和均匀连续的非标准特征证明了拓扑等度连续和均匀连续之间的关系. 相似文献
4.
本文引进并研究了Furstenberg族意义下的处处混沌与等度连续的概念.如果一个动力系统是F_1-敏感和F_2-可达的,则称之为(F_1,F_2)-处处混沌的,其中F_1与F_2是Furstenberg族.一个动力系统(X,f)被称为F_1-敏感的,是指存在7>0使得对任意x∈X及x的任意开邻域存在y∈U,有{n∈Z_+:d(f~n(x),f~n(y))>τ}∈F_1成立.一个动力系统(X,f)被称为F_2-可达的,是指对任意的s>O及X的任意非空开集U,V,存在x∈U,y∈V使得{n∈Z_+:d(f~n(x),f~n(y))<ε}∈F_1成立.一个动力系统被称为F-等度连续的,是指对任意的ε>0,存在δ>0,当d(x,y)<δ时有{n∈Z_+:d(f~n(x),f~n(y))<ε}∈F成立,其中F是一个Furstenberg族. 相似文献
5.
设W为华沙圈,f:W→W为连续映射.本文得到了f为distal的一个刻画并且讨论了f的distality与等度连续性的关系.证明了:(i)f是distal的当且仅当f为恒等映射.(ii)如果f为满射,则f是distal的当且仅当f为等度连续的. 相似文献
6.
7.
8.
9.
等度连续与POTP 总被引:3,自引:0,他引:3
赵俊玲 《高校应用数学学报(A辑)》2002,17(2):179-181
本文证明了在紧致连通的度量空间中,等度连续的自映射不具有POTP。 相似文献
10.
11.
V.F. Demyanov introduced exhausters for the study of nonsmooth functions. These are families of convex compact sets that enable one to represent the main part of the increment of a considered function in a neighborhood of the studied point as MaxMin or MinMax of linear functions. Optimality conditions were described in terms of these objects. This provided a way for constructing new algorithms for solving nondifferentiable optimization problems. Exhausters are defined not uniquely. It is obvious that the smaller an exhauster, the less are the computational expenses when working with it. Thus, the problem of reduction of an available family arises. For the first time, this problem was considered by V.A. Roshchina. She proposed conditions for minimality and described some methods of reduction in the case when these conditions are not satisfied. However, it turned out that the exhauster mapping is not continuous in the Hausdorff metrics, which leads to the problems with convergence of numerical methods. To overcome this difficulty, Demyanov proposed the notion of coexhausters. These objects enable one to represent the main part of the increment of the considered function in a neighborhood of the studied point in the form of MaxMin or MinMax of affine functions. One can define a class of functions with the continuous coexhauster mapping. Optimality conditions can be stated in terms of these objects too. But coexhausters are also defined not uniquely. The problem of reduction of coexhausters is considered in this paper for the first time. Definitions of minimality proposed by Roshchina are used. In contrast to ideas proposed in the works of Roshchina, the minimality conditions and the technique of reduction developed in this paper have a clear and transparent geometric interpretation. 相似文献
12.
William A. Veech 《Israel Journal of Mathematics》1975,21(2-3):233-239
IfN is the nilpotent constituent of an Iwasawa decomposition of the semi-simple groupG (finite center and no compact factors), it is proved thatN acts minimally onG/Γ for every uniform lattice Γ ?G, generalizing theorems of Hedlund and L. Greenberg. 相似文献
13.
14.
15.
16.
We give a complete classification of the locally finite groups that are minimal with respect to Sylow-permutability being intransitive. 相似文献
17.
A. N. Starkov 《Mathematical Notes》1999,66(2):233-239
Consider a connected Lie groupG, a lattice Γ inG, a connected subgroupH ofG, and the adjoint representation Ad ofG on its Lie algebra g. Suppose that Ad(H) splits into a semidirect product of a reductive subgroup and the unipotent radical. We prove that the minimality of the
leftH-action onG/Γ then implies its unique ergodicity. Simultaneously, we suggest a reduction of the study of finite ergodic measures for
an arbitrary action (G/Γ,H), where the subgroupH∈G is connected and Γ∈G is discrete, to the case of an Abelian subgroupH.
Translated fromMatematicheskie Zametki, Vol. 66, No. 2, pp. 293–301, August, 1999. 相似文献
18.
19.
20.
We study the relationship between minimality and unique ergodicity for adic transformations. We show that three is the smallest
alphabet size for a unimodular “adic counterexample”, an adic transformation which is minimal but not uniquely ergodic. We
construct a specific family of counterexamples built from (3 × 3) nonnegative integer matrix sequences, while showing that
no such (2 × 2) sequence is possible. We also consider (2 × 2) counterexamples without the unimodular restriction, describing
two families of such maps.
Though primitivity of the matrix sequence associated to the transformation implies minimality, the converse is false, as shown
by a further example: an adic transformation with (2 × 2) stationary nonprimitive matrix, which is both minimal and uniquely
ergodic. 相似文献