The iterated Aluthge Transforms of compact operators

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteur principal: Bala, Neeru
Format: Preprint
Publié: 2026
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866911642275545088
author Bala, Neeru
author_facet Bala, Neeru
contents Let $T$ be a bounded linear operator on a Hilbert space. Then the Aluthge transform $ΔT$ and the sequence $(Δ^nT)$ of Aluthge iterates of $T$ are defined by \begin{align*} ΔT=|T|^{1/2}U|T|^{1/2},\,Δ^0T=T,\,Δ^nT=Δ(Δ^{n-1}T),\,n\in\mathbb{N}. \end{align*} We prove that $Δ$ is a continuous map on the space of all compact operators on a separable Hilbert space with respect to the norm topology and using this result we also prove that the sequence $(Δ^nT)$ converges in the norm topology to a normal compact operator for every compact operator $T$ on a separable Hilbert space. This gives an affirmative answer to two questions raised by Jung, Ko and Pearcy \cite{Pearcy2} for compact operators.
format Preprint
id arxiv_https___arxiv_org_abs_2602_07916
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle The iterated Aluthge Transforms of compact operators
Bala, Neeru
Functional Analysis
47B02, 47B07
Let $T$ be a bounded linear operator on a Hilbert space. Then the Aluthge transform $ΔT$ and the sequence $(Δ^nT)$ of Aluthge iterates of $T$ are defined by \begin{align*} ΔT=|T|^{1/2}U|T|^{1/2},\,Δ^0T=T,\,Δ^nT=Δ(Δ^{n-1}T),\,n\in\mathbb{N}. \end{align*} We prove that $Δ$ is a continuous map on the space of all compact operators on a separable Hilbert space with respect to the norm topology and using this result we also prove that the sequence $(Δ^nT)$ converges in the norm topology to a normal compact operator for every compact operator $T$ on a separable Hilbert space. This gives an affirmative answer to two questions raised by Jung, Ko and Pearcy \cite{Pearcy2} for compact operators.
title The iterated Aluthge Transforms of compact operators
topic Functional Analysis
47B02, 47B07
url https://arxiv.org/abs/2602.07916