{ "id": "1203.1134", "version": "v1", "published": "2012-03-06T08:49:06.000Z", "updated": "2012-03-06T08:49:06.000Z", "title": "A note on property (gb) and perturbations", "authors": [ "Qingping Zeng", "Huaijie Zhong" ], "comment": "10 pages", "journal": "Abstract and Applied Analysis Volume 2012 (2012), Article ID 523986, 10 pages", "doi": "10.1155/2012/523986", "categories": [ "math.FA" ], "abstract": "An operator $T \\in \\mathcal{B}(X)$ defined on a Banach space $X$ satisfies property $(gb)$ if the complement in the approximate point spectrum $\\sigma_{a}(T)$ of the upper semi-B-Weyl spectrum $\\sigma_{SBF_{+}^{-}}(T)$ coincides with the set $\\Pi(T)$ of all poles of the resolvent of $T$. In this note we continue to study property $(gb)$ and the stability of it, for a bounded linear operator $T$ acting on a Banach space, under perturbations by nilpotent operators, by finite rank operators, by quasi-nilpotent operators commuting with $T$. Two counterexamples show that property $(gb)$ in general is not preserved under commuting quasi-nilpotent perturbations or commuting finite rank perturbations.", "revisions": [ { "version": "v1", "updated": "2012-03-06T08:49:06.000Z" } ], "analyses": { "subjects": [ "47A10", "47A11", "47A53", "47A55" ], "keywords": [ "banach space", "approximate point spectrum", "upper semi-b-weyl spectrum", "finite rank operators", "commuting finite rank perturbations" ], "tags": [ "journal article" ], "publication": { "publisher": "Hindawi", "journal": "Adv. High Energ. Phys." }, "note": { "typesetting": "TeX", "pages": 10, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1203.1134Z" } } }