{ "id": "math/0501092", "version": "v3", "published": "2005-01-06T20:39:01.000Z", "updated": "2005-05-08T15:14:29.000Z", "title": "Operator amenability of the Fourier algebra in the cb-multiplier norm", "authors": [ "Brian E. Forrest", "Volker Runde", "Nico Spronk" ], "comment": "LaTeX2e; 18 pages; cleaned up a bit", "journal": "Canadian J. Math. 59 (2007), 966-980", "categories": [ "math.FA", "math.OA" ], "abstract": "Let $G$ be a locally compact group, and let $A_\\cb(G)$ denote the closure of $A(G)$, the Fourier algebra of $G$, in the space of completely bounded multipliers of $A(G)$. If $G$ is a weakly amenable, discrete group such that $\\cstar(G)$ is residually finite-dimensional, we show that $A_\\cb(G)$ is operator amenable. In particular, $A_\\cb(F_2)$ is operator amenable even though $F_2$, the free group in two generators, is not an amenable group. Moreover, we show that, if $G$ is a discrete group such that $A_\\cb(G)$ is operator amenable, a closed ideal of $A(G)$ is weakly completely complemented in $A(G)$ if and only if it has an approximate identity bounded in the cb-multiplier norm.", "revisions": [ { "version": "v3", "updated": "2005-05-08T15:14:29.000Z" } ], "analyses": { "subjects": [ "43A22", "43A30", "46H25", "46J10", "46J40", "46L07", "47L25" ], "keywords": [ "fourier algebra", "cb-multiplier norm", "operator amenability", "discrete group", "operator amenable" ], "tags": [ "journal article" ], "note": { "typesetting": "LaTeX", "pages": 18, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2005math......1092F" } } }