On (n,k)-quasiparanormal operators

• Autorzy: Jiangtao Yuan , Guoxing Ji
• Języki publikacji: EN

Abstrakty

EN

Let T be a bounded linear operator on a complex Hilbert space 𝓗. For positive integers n and k, an operator T is called (n,k)-quasiparanormal if
$||T^{1+n}(T^{k}x)||^{1/(1+n)} ||T^{k}x||^{n/(1+n)} ≥ ||T(T^{k}x)||$ for x ∈ 𝓗.
The class of (n,k)-quasiparanormal operators contains the classes of n-paranormal and k-quasiparanormal operators. We consider some properties of (n,k)-quasiparanormal operators: (1) inclusion relations and examples; (2) a matrix representation and SVEP (single valued extension property); (3) ascent and Bishop's property (β); (4) quasinilpotent part and Riesz idempotents for k-quasiparanormal operators.

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Studia Mathematica
• Rocznik: 2012
• Tom: 209
• Numer: 3
• Strony: 289-301

Daty

wydano

2012

Twórcy

autor

Jiangtao Yuan

• College of Mathematics and Information Science, Shaanxi Normal University, Xian 710062, China
• School of Mathematics and Information Science, Henan Polytechnic University, Jiaozuo 454000, Henan Province, China

autor

Guoxing Ji

• College of Mathematics and Information Science, Shaanxi Normal University, Xian 710062, China

Identyfikatory

DOI

10.4064/sm209-3-6