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 lsi1" class="mathmlsrc">lass="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0019357715000786&_mathId=si1.gif&_user=111111111&_pii=S0019357715000786&_rdoc=1&_issn=00193577&md5=e620a36814070b24021c7fa91e8f252d" title="Click to view the MathML source">Alass="mathContainer hidden">lass="mathCode">low="scroll">A which is subjected to structured perturbation of the form lsi2" class="mathmlsrc">lass="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0019357715000786&_mathId=si2.gif&_user=111111111&_pii=S0019357715000786&_rdoc=1&_issn=00193577&md5=a5c75a3af2c222b01dd602e1ff591259" title="Click to view the MathML source">A⟶A+CDBlass="mathContainer hidden">lass="mathCode">low="scroll">A⟶A+CDB where lsi3" class="mathmlsrc">lass="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0019357715000786&_mathId=si3.gif&_user=111111111&_pii=S0019357715000786&_rdoc=1&_issn=00193577&md5=4ede1ad703ec684adb7bbf8b90e3d79c" title="Click to view the MathML source">Blass="mathContainer hidden">lass="mathCode">low="scroll">B, lsi4" class="mathmlsrc">lass="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0019357715000786&_mathId=si4.gif&_user=111111111&_pii=S0019357715000786&_rdoc=1&_issn=00193577&md5=4d7f1043a23c6712b8440c24e01a59fe" title="Click to view the MathML source">Class="mathContainer hidden">lass="mathCode">low="scroll">C are given bounded operators and lsi5" class="mathmlsrc">lass="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0019357715000786&_mathId=si5.gif&_user=111111111&_pii=S0019357715000786&_rdoc=1&_issn=00193577&md5=8dc6b984d2e85995caa9bd90fee5ded8" title="Click to view the MathML source">Dlass="mathContainer hidden">lass="mathCode">low="scroll">D is unknown disturbance operator that satisfies lsi6" class="mathmlsrc">lass="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0019357715000786&_mathId=si6.gif&_user=111111111&_pii=S0019357715000786&_rdoc=1&_issn=00193577&md5=efd45c86083613eb88e3b76e512d6550" title="Click to view the MathML source">‖D‖<εlass="mathContainer hidden">lass="mathCode">low="scroll">‖D‖<ε for a given lsi7" class="mathmlsrc">lass="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0019357715000786&_mathId=si7.gif&_user=111111111&_pii=S0019357715000786&_rdoc=1&_issn=00193577&md5=d89d750dcd4962f1c253356323803411" title="Click to view the MathML source">ε>0lass="mathContainer hidden">lass="mathCode">low="scroll">ε>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.