Fixed Simplex Property for Retractable Complexes

<p>Abstract</p> <p>Retractable complexes are defined in this paper. It is proved that they have the fixed simplex property for simplicial maps. This implies the theorem of Wallace and the theorem of Rival and Nowakowski for finite trees: every simplicial map transforming vertices o...

Full description

Bibliographic Details
Main Authors: Zapart Anna, Idzik Adam
Format: Article
Language:English
Published: SpringerOpen 2010-01-01
Series:Fixed Point Theory and Applications
Online Access:http://www.fixedpointtheoryandapplications.com/content/2010/303640
Description
Summary:<p>Abstract</p> <p>Retractable complexes are defined in this paper. It is proved that they have the fixed simplex property for simplicial maps. This implies the theorem of Wallace and the theorem of Rival and Nowakowski for finite trees: every simplicial map transforming vertices of a tree into itself has a fixed vertex or a fixed edge. This also implies the Hell and Ne&#353;et&#345;il theorem: any endomorphism of a dismantlable graph fixes some clique. Properties of recursively contractible complexes are examined.</p>
ISSN:1687-1820
1687-1812