Proximinality in geodesic spaces

Let X be a complete CAT(0) space with the geodesic extension property and Alexandrov curvature bounded below. It is shown that if C is a closed subset of X, then the set of points of X which have a unique nearest point in C is Gδ and of the second Baire category in X. If, in addition, C is bounded,...

Full description

Saved in:
Bibliographic Details
Main Authors: A. Kaewcharoen, W. A. Kirk
Format: Article
Language:English
Published: Wiley 2006-01-01
Series:Abstract and Applied Analysis
Online Access:http://dx.doi.org/10.1155/AAA/2006/43591
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Let X be a complete CAT(0) space with the geodesic extension property and Alexandrov curvature bounded below. It is shown that if C is a closed subset of X, then the set of points of X which have a unique nearest point in C is Gδ and of the second Baire category in X. If, in addition, C is bounded, then the set of points of X which have a unique farthest point in C is dense in X. A proximity result for set-valued mappings is also included.
ISSN:1085-3375
1687-0409