Fixed Point Theory and Applications
Volume 2006 (2006), Article ID 82080, 13 pages

Nonexpansive mappings defined on unbounded domains

A. Kaewcharoen1 and W. A. Kirk2

1Department of Mathematics, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand
2Department of Mathematics, The University of Iowa, Iowa City 52242-1419, IA, USA

Received 18 January 2006; Accepted 23 January 2006

Copyright © 2006 A. Kaewcharoen and W. A. Kirk. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


We obtain fixed point theorems for nonexpansive mappings defined on unbounded sets. Our assumptions are weaker than the asymptotically contractive condition recently introduced by Jean-Paul Penot.