The Essential Spectrum of the Essentially Isometric Operator
| dc.authorscopusid | 25123084500 | |
| dc.contributor.author | Mustafayev, H. S. | |
| dc.date.accessioned | 2025-05-10T17:45:31Z | |
| dc.date.available | 2025-05-10T17:45:31Z | |
| dc.date.issued | 2014 | |
| dc.department | T.C. Van Yüzüncü Yıl Üniversitesi | en_US |
| dc.department-temp | Yuzuncu Yil Univ, Fac Sci, Dept Math, TR-65080 Van, Turkey | en_US |
| dc.description.abstract | Let T be a contraction on a complex, separable, infinite dimensional Hilbert space and let sigma(T) (resp. sigma(e)(T)) be its spectrum (resp. essential spectrum). We assume that T is an essentially isometric operator; that is, I-H - T* T is compact. We show that if D\sigma T(T) not equal phi, then for every f from the disc-algebra sigma(e)( f(T)) = f( sigma(e)(T)), where D is the open unit disc. In addition, if T lies in the class C-0. boolean OR C-.0, then sigma(e)( f(T)) = f( sigma(T) boolean AND Gamma), where Gamma is the unit circle. Some related problems are also discussed. | en_US |
| dc.description.woscitationindex | Science Citation Index Expanded | |
| dc.identifier.doi | 10.4153/CMB-2012-016-1 | |
| dc.identifier.endpage | 158 | en_US |
| dc.identifier.issn | 0008-4395 | |
| dc.identifier.issn | 1496-4287 | |
| dc.identifier.issue | 1 | en_US |
| dc.identifier.scopus | 2-s2.0-84892640346 | |
| dc.identifier.scopusquality | Q3 | |
| dc.identifier.startpage | 145 | en_US |
| dc.identifier.uri | https://doi.org/10.4153/CMB-2012-016-1 | |
| dc.identifier.uri | https://hdl.handle.net/20.500.14720/16379 | |
| dc.identifier.volume | 57 | en_US |
| dc.identifier.wos | WOS:000331418000019 | |
| dc.identifier.wosquality | Q3 | |
| dc.institutionauthor | Mustafayev, H. S. | |
| dc.language.iso | en | en_US |
| dc.publisher | Canadian Mathematical Soc | en_US |
| dc.relation.publicationcategory | Makale - Uluslararası Hakemli Dergi - Kurum Öğretim Elemanı | en_US |
| dc.rights | info:eu-repo/semantics/openAccess | en_US |
| dc.subject | Hilbert Space | en_US |
| dc.subject | Contraction | en_US |
| dc.subject | Essentially Isometric Operator | en_US |
| dc.subject | (Essential) Spectrum | en_US |
| dc.subject | Functional Calculus | en_US |
| dc.title | The Essential Spectrum of the Essentially Isometric Operator | en_US |
| dc.type | Article | en_US |