Weyl's theorem for commuting tuples of paranormal and ∗-paranormal operators

• Autorzy: Bala Neru , Ramesh G.

Identyfikatory

DOI

10.4064/ba210325-13-6

• Języki publikacji: EN

Abstrakty

EN

We show that a commuting pair T=(T₁,T₂) of ∗-paranormal operators T₁ and T₂ with quasitriangular property satisfies Weyl’s theorem-I, that is, σT(T)∖σTW(T)=π00(T) and a commuting pair of paranormal operators satisfies Weyl’s theorem-II, that is, σT(T)∖ω(T)=π00(T), where σT(T),σTW(T),ω(T) and π00(T) are the Taylor spectrum, the Taylor Weyl spectrum, the joint Weyl spectrum and the set of isolated eigenvalues of T with finite multiplicity, respectively. Moreover, we prove that Weyl’s theorem-II holds for f(T), where T is a commuting pair of paranormal operators and f is an analytic function in a neighbourhood of

Słowa kluczowe

EN

paranormal operator; Taylor invertible; Taylor Fredholm; Weyl’s theorem

• Wydawca: Instytut Matematyczny PAN
• Czasopismo: Bulletin of the Polish Academy of Sciences. Mathematics
• Rocznik: 2021
• Tom: Vol. 69, no. 1
• Strony: 69--86
• Opis fizyczny: Bibliogr. 17 poz.

Twórcy

autor

Bala Neru

• Department of Mathematics, Indian Institute of Technology - Hyderabad, Kandi, Sangareddy, Telangana, India 502 285

• https://orcid.org/0000-0002-1729-4848

autor

Ramesh G.

• Department of Mathematics, Indian Institute of Technology - Hyderabad, Kandi, Sangareddy, Telangana, India 502 285

• https://orcid.org/0000-0002-8005-3262

Bibliografia

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