On approximate point joint spectrum of p-hyponormal and log-hyponormal operators

• Autorzy: Chō M. , Sołtysiak A. , Yamazaki T.
• Języki publikacji: EN

Abstrakty

EN

We show that the approximate point joint spectrum of an arbitrary n-tuple of p-hyponormal (or log-hyponormal) operators can be obtained from the spectral set 7 introduced by Mclntosh and Pryde. This is a generalization of a result proved by the second named author for hyponormal operators. We also obtain a similar result for log-hyponormal operators based on the polar decomposition.

Słowa kluczowe

EN

approximate point spectrum; spectral set gamma; spectral set γ; p-hyponormal operator; log-hyponormal operator

• Wydawca: Polskie Towarzystwo Matematyczne
• Czasopismo: Annales Societatis Mathematicae Polonae. Seria 1: Commentationes Mathematicae
• Rocznik: 2003
• Tom: [Z] 43(1)
• Strony: 33--41
• Opis fizyczny: Bibliogr. 20 poz.

Twórcy

autor

Chō M.

• Department of Mathematics, Kanagawa University, Yokohama 221-8686, Japan

autor

Sołtysiak A.

• Faculty of Mathematics and Computer Science, Adam Mickiewicz University, ul. Umultowska 87, 61-614 Poznań, Poland

autor

Yamazaki T.

• Department of Mathematics, Kanagawa University, Yokohama 221-8686, Japan

Bibliografia

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