Local spectral theory for 2×2 operator matrices

We discuss the spectral properties of the operator MC∈ℒ(X⊕Y) defined by MC:=(AC0B), where A∈ℒ(X), B∈ℒ(Y), C∈ℒ(Y,X), and X, Y are complex Banach spaces. We prove that (SA∗∩SB)∪σ(MC)=σ(A)∪σ(B) for all C∈ℒ(Y,X). This allows us to give a partial positive answer to Question 3 of Du and Jin (1994) and gen...

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Bibliographic Details
Main Authors: H. Elbjaoui, E. H. Zerouali
Format: Article
Language:English
Published: Hindawi Limited 2003-01-01
Series:International Journal of Mathematics and Mathematical Sciences
Online Access:http://dx.doi.org/10.1155/S0161171203012043