{ "id": "0805.0209", "version": "v1", "published": "2008-05-02T11:08:09.000Z", "updated": "2008-05-02T11:08:09.000Z", "title": "Application of topological radicals to calculation of joint spectral radii", "authors": [ "Victor S. Shulman", "Yuri V. Turovskii" ], "categories": [ "math.FA", "math.SP" ], "abstract": "It is shown that the joint spectral radius $\\rho(M)$ of a precompact family $M$ of operators on a Banach space $X$ is equal to the maximum of two numbers: the joint spectral radius $\\rho_{e}(M)$ of the image of $M$ in the Calkin algebra and the Berger-Wang radius $r(M)$ defined by the formula \\[ r(M)=\\underset{n\\to\\infty}{\\limsup}(\\sup\\left\\{\\rho(a):a\\in M^{n}\\right\\} ^{1/n}) . \\] Some more general Banach-algebraic results of this kind are also proved. The proofs are based on the study of special radicals on the class of Banach algebras.", "revisions": [ { "version": "v1", "updated": "2008-05-02T11:08:09.000Z" } ], "analyses": { "subjects": [ "47D03", "46H05" ], "keywords": [ "joint spectral radius", "topological radicals", "application", "calculation", "general banach-algebraic results" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2008arXiv0805.0209S" } } }