B-fredholm and spectral properties for multipliers in Banach algebras

被引:5
作者
Berkani M. [1 ]
Arroud A. [1 ]
机构
[1] Département de Mathématiques, Groupe d'Analyse et Théorie des Opérateurs (G.A.T.O), Université Mohammed I, Faculté des Sciences, Oujda
关键词
B-Fredholm operators; Banach Algebras; generalized Weyl's theorem; Multipliers; Weyl's theorem;
D O I
10.1007/BF02874778
中图分类号
学科分类号
摘要
The main purpose of this paper is to study spectral and B-Fredholm properties of a multiplier T acting on a semi-simple regular tauberian commutative Banach algebra A. We show that T is a B-Fredholm operator if and only if T is a semi B-Fredholm operator, and in this case we have the index ind(T)=0. Moreover we give some spectral properties for multipliers. Spectral mapping theorems for the Weyl's and B-Weyl spectrum of a multiplier are also considered. Furthermore we show that Weyl's theorem and generalized Weyl's theorem hold for a multiplier T. Finally we give sufficient conditions for a multiplier to be a product of an invertible and an idempotent operators. © 2006 Springer.
引用
收藏
页码:385 / 397
页数:12
相关论文
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