期刊信息
- 刊名： 河北师范大学学报（自然科学版）Journal of Hebei Normal University (Natural Science)
- 主办： 河北师范大学
- ISSN： 1000-5854
- CN： 13-1061/N
- 中国科技核心期刊
- 中国期刊方阵入选期刊
- 中国高校优秀科技期刊
- 华北优秀期刊
- 河北省优秀科技期刊
Two Open Problems Aboutλ -property
摘要/Abstract
摘要：
有些赋范空间的闭单位球具有称作“λ-性质”的几何特征,即闭单位球上的任一点x均可表示为闭单位球端点e和点y(‖y‖≤1)的凸组合.举例说明了若X有λ-性质,那么l∞(X)和X未必有λ-性质,从而证明X和l∞(X),X*在λ-性质方面不存在必然联系
Abstract：
There are many normed spaces, whose closed unit balls have the following geometric property,calledλ -property,in common,each member x of the unit ball is a convex combination,which is an extreme point e of the unit ball and a vector y, where‖ y‖≤ 1 and e is assigned a positive weight.two open problems about λ -property had been proved : though x has the λ -property,l∞ (X ) and X* then need not have theλ -property.
关键词
Key words：
λ-property
;
space of l∞(X)
;
space of X*