Countable contraction mappings in metric spaces: Invariant Sets and Measures

We consider a complete metric space (X, d) and a countable number of contraction mappings on X, F = {Fi : i ∈ N}. We show the existence of a smallest invariant set (with respect to inclusion) for F. If the maps Fi are of the form Fi(x) = rix + bi on X = R d , we prove a converse of the classic resul...

Descripción completa

Detalles Bibliográficos
Autores: Barrozo, María Fernanda, Molter, Ursula Maria
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2014
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/18774
Acceso en línea:http://hdl.handle.net/11336/18774
Access Level:acceso abierto
Palabra clave:Countable Iterated Function Systems
Invariant Measure
Atractor
https://purl.org/becyt/ford/1.1
https://purl.org/becyt/ford/1
Descripción
Sumario:We consider a complete metric space (X, d) and a countable number of contraction mappings on X, F = {Fi : i ∈ N}. We show the existence of a smallest invariant set (with respect to inclusion) for F. If the maps Fi are of the form Fi(x) = rix + bi on X = R d , we prove a converse of the classic result on contraction mappings, more precisely, there exists a unique bounded invariant set if and only if r = supi ri is strictly smaller than 1. Further, if ρ = {ρk}k∈N is a probability sequence, we show that if there exists an invariant measure for the system (F, ρ), then its support must be precisely this smallest invariant set. If in addition there exists any bounded invariant set, this invariant measure is unique, even though there may be more than one invariant set.