Some results on generalized finite operators and range kernel orthogonality in Hilbert spaces

• Autorzy: Mesbah Nadia , Messaoudene Hadia , Alharbi Asma

Identyfikatory

DOI

10.1515/dema-2021-0037

• Języki publikacji: EN

Abstrakty

EN

Let be a complex Hilbert space and B(H) denotes the algebra of all bounded linear operators acting on H. In this paper, we present some new pairs of generalized finite operators. More precisely, new pairs of operators (A, B) ∈ B(H) × B(H) satisfying: ∥ AX – XB − I∥ ≥ 1, for all X ∈ B(H). An example under which the class of such operators is not invariant under similarity orbit is given. Range kernel orthogonality of generalized derivation is also studied.

Słowa kluczowe

EN

finite operator; numerical range; orthogonality; class R1

PL

operatory skończone; numeryczny zbiór wartości; ortogonalność

• Wydawca: De Gruyter
• Czasopismo: Demonstratio Mathematica
• Rocznik: 2021
• Tom: Vol. 54, nr 1
• Strony: 318--325
• Opis fizyczny: Bibliogr. 19 poz.

Twórcy

autor

Mesbah Nadia

• Department of Mathematics and Computer Science, Laboratory of Mathematics, Informatics and Systems (LAMIS), Larbi Tebessi University, Tebessa, Algeria

autor

Messaoudene Hadia

• Faculty of Economics Sciences and Management, Laboratory of Mathematics, Informatics and Systems (LAMIS), Larbi Tebessi University, Tebessa, Algeria

autor

Alharbi Asma

• Department of Mathematics, College of Sciences and Arts, Ar Rass, Qassim University, Saudi Arabia

Bibliografia

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Uwagi

PL

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2021).