Convergence of the iterated Aluthge transform sequence for diagonalizable matrices

Given an r × r complex matrix T, if T = U | T | is the polar decomposition of T, then, the Aluthge transform is defined byΔ (T) = | T |1 / 2 U | T |1 / 2 . Let Δn (T) denote the n-times iterated Aluthge transform of T, i.e. Δ0 (T) = T and Δn (T) = Δ (Δn - 1 (T)), n ∈ N. We prove that the sequence {Δ...

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Detalhes bibliográficos
Autores: Antezana, Jorge Abel, Pujals, Enrique, Stojanoff, Demetrio
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2007
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/99841
Acesso em linha:http://hdl.handle.net/11336/99841
Access Level:acceso abierto
Palavra-chave:ALUTHGE TRANSFORM
POLAR DECOMPOSITION
SIMILARITY ORBIT
STABLE MANIFOLD THEOREM
https://purl.org/becyt/ford/1.1
https://purl.org/becyt/ford/1
Descrição
Resumo:Given an r × r complex matrix T, if T = U | T | is the polar decomposition of T, then, the Aluthge transform is defined byΔ (T) = | T |1 / 2 U | T |1 / 2 . Let Δn (T) denote the n-times iterated Aluthge transform of T, i.e. Δ0 (T) = T and Δn (T) = Δ (Δn - 1 (T)), n ∈ N. We prove that the sequence {Δn (T)}n ∈ N converges for every r × r diagonalizable matrix T. We show that the limit Δ∞ (ṡ) is a map of class C∞ on the similarity orbit of a diagonalizable matrix, and on the (open and dense) set of r × r matrices with r different eigenvalues.