Hostname: page-component-586b7cd67f-2plfb Total loading time: 0 Render date: 2024-11-25T02:40:58.284Z Has data issue: false hasContentIssue false

The weak drop property on closed convex sets

Published online by Cambridge University Press:  09 April 2009

Pei-Kee Lin
Affiliation:
Memphis State University, Memphis TN 38152, USA
Xintai Yu
Affiliation:
East China Normal University, Shanghai, China
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Recall a closed convex set C is said to have the weak drop property if for every weakly sequentially closed set A disjoint from C there exists xA such that co({x} ∩ C) ∪ A = {x}. Giles and Kutzarova proved that every bounded closed convex set with the weak drop property is weakly compact. In this article, we show that if C is an unbounded closed convex set of X with the weak drop property, then C has nonempty interior and X is a reflexive space.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1994

References

[1]Daneš, J., ‘A geometric theorem useful in nonlinear functional analysis’, Boll. Un. Mat. Ital. 6 (1972), 369375.Google Scholar
[2]Diestel, J., Sequences and series in Banach spaces (Springer-Verlag, New York Berlin Heidelberg Tokyo, 1984).Google Scholar
[3]Giles, J. R., Sims, B. and Yorke, A. C., ‘On the drop and weak drop properties for a Banach space’, Bull. Austral. Math. Soc. 41 (1990), 503507.Google Scholar
[4]Giles, R. and Kutzarova, D. N., ‘Characterisation of drop and weak drop properties for closed bounded convex sets’, Bull. Austral. Math. Soc. 43 (1991), 377385.Google Scholar
[5]Kutzarova, D. N. and Rolewicz, S., ‘Drop property for convex sets’, Journal Archiv der Mathematik 56 (1991), 501511.Google Scholar
[6]Lin, P. K., ‘Some remarks of the drop property’, Proc. Amer. Math. Soc. 115 (1992), 441446.Google Scholar
[7]Phelps, R. R., ‘Weak* support points of convex sets in E*’, Israel J. Math. 2 (1964), 177182.Google Scholar