A VECTOR-VALUED VERSION OF RUSSO-DYE THEOREM

被引:0
作者
Navarro-Pascual, J. C. [1 ]
Sanchez-Lirola, M. G. [1 ]
机构
[1] Univ Almeria, Dept Algebra & Anal Matemat, Almeria 04120, Spain
关键词
Mappings into spheres; uniformly convex normed space; extreme point; semi-circumference inequality; OPERATORS;
D O I
10.1142/S021919970900365X
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
In this paper, we will study the extremal structure of the unit ball of U(M, X), the space of uniformly continuous and bounded functions, from a not necessarily compact metric space M into a normed space X. Concretely, if X is uniformly convex and dim X >= 2, where dim X denotes the dimension of X as a real vector space, it is proved that every element y in U(M, X), with parallel to y parallel to < 1, is a convex combination of a finite number of extreme points of the unit ball. As a result, the unit ball of U(M, X) coincides with the closed-convex hull of its extreme points.
引用
收藏
页码:1035 / 1048
页数:14
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