{ "id": "2103.14478", "version": "v1", "published": "2021-03-26T14:06:42.000Z", "updated": "2021-03-26T14:06:42.000Z", "title": "The Operator Norm on Weighted Discrete Semigroup Algebras $\\ell^1(S, ω)$", "authors": [ "H. V. Dedania", "J. G. Patel" ], "comment": "7 pages", "categories": [ "math.FA" ], "abstract": "Let $\\omega$ be a weight on a right cancellative semigroup $S$. Let $\\|\\cdot\\|_{\\omega}$ be the weighted norm on the weighted discrete semigroup algebra $\\ell^1(S, \\omega)$. In this paper, we prove that the weight $\\omega$ satisfies F-property if and only if the operator norm $\\| \\cdot \\|_{\\omega op}$ of $\\| \\cdot \\|_{\\omega}$ is exactly equal to another weighted norm $\\| \\cdot \\|_{\\widetilde{\\omega}_1}$ [Theorem 2.5 ($iii$)]. Though its proof is elementary, the result is unexpectedly surprising. In particular, $\\| \\cdot \\|_{1 op}$ is same as $\\| \\cdot \\|_1$ on $\\ell^1(S)$. Moreover, various examples are discussed to understand the relating among $\\| \\cdot \\|_{\\omega op}$, $\\| \\cdot \\|_{\\omega}$, and $\\ell^1(S, \\omega)$.", "revisions": [ { "version": "v1", "updated": "2021-03-26T14:06:42.000Z" } ], "analyses": { "subjects": [ "46H05", "43A20" ], "keywords": [ "weighted discrete semigroup algebra", "operator norm", "weighted norm", "right cancellative semigroup", "satisfies f-property" ], "note": { "typesetting": "TeX", "pages": 7, "language": "en", "license": "arXiv", "status": "editable" } } }