On a characterization of the structured Wolf, Schechter and Browder essential pseudospectra

详细信息    查看全文

• 作者：Asrar Elleuch ^{asrar_elleuch@yahoo.fr" class="auth_mail" title="E-mail the corresponding author} ; Aref Jeribi ; ^{Aref.Jeribi@fss.rnu.tn" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Fredholm perturbation ; Wolf ; Schechter and Browder essential spectra ; Structured pseudospectra
• 刊名：Indagationes Mathematicae
• 出版年：2016
• 出版时间：January 2016
• 年：2016
• 卷：27
• 期：1
• 页码：212-224
• 全文大小：212 K

文摘

In this paper, we concern ourselves with essential spectra of an operator 252d" title="Click to view the MathML source">A$A$ which is subjected to structured perturbation of the form A⟶A+CDB$A⟶A+CDB$ where B$B$, C$C$ are given bounded operators and D$D$ is unknown disturbance operator that satisfies ‖D‖<ε$\Vert D\Vert <\epsilon$ for a given ε>0$\epsilon >0$. Thereby, we investigate the structured essential pseudospectra of the sum of two operators acting on a Banach space. Furthermore, we establish characterizations of the structured Schechter essential pseudospectrum of a closed, densely defined linear operator.