Fixed point theorems in CAT(0) spaces and â„Â-trees

We show that if U is a bounded open set in a complete CAT(0) space X, and if f:U¯→X is nonexpansive, then f always has a fixed point if there exists p∈U such that x∉[p,f(x)) for all x∈∂U. It is also shown that if K is a geodesically bounded closed convex subset of a compl...

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Bibliographic Details
Main Author: W. A. Kirk
Format: Article
Language:English
Published: SpringerOpen 2004-12-01
Series:Fixed Point Theory and Applications
Online Access:http://dx.doi.org/10.1155/S1687182004406081