{ "id": "math/0206041", "version": "v6", "published": "2002-06-05T14:56:32.000Z", "updated": "2002-12-28T17:59:28.000Z", "title": "Abstract harmonic analysis, homological algebra, and operator spaces", "authors": [ "Volker Runde" ], "comment": "12 pages; a survey article; typos removed, references updated", "journal": "Contemp. Math. 328 (2003), 263-274", "categories": [ "math.FA", "math.KT", "math.OA" ], "abstract": "In 1972, B. E. Johnson proved that a locally compact group $G$ is amenable if and only if certain Hochschild cohomology groups of its convolution algebra $L^1(G)$ vanish. Similarly, $G$ is compact if and only if $L^1(G)$ is biprojective: In each case, a classical property of $G$ corresponds to a cohomological propety of $L^1(G)$. Starting with the work of Z.-J. Ruan in 1995, it has become apparent that in the non-commutative setting, i.e. when dealing with the Fourier algebra $A(G)$ or the Fourier-Stieltjes algebra $B(G)$, the canonical operator space structure of the algebras under consideration has to be taken into account: In analogy with Johnson's result, Ruan characterized the amenable locally compact groups $G$ through the vanishing of certain cohomology groups of $A(G)$. In this paper, we give a survey of historical developments, known results, and current open problems.", "revisions": [ { "version": "v6", "updated": "2002-12-28T17:59:28.000Z" } ], "analyses": { "subjects": [ "22D15", "22D25", "43A20", "43A30", "46H20", "46H25", "46L07", "46M18", "46M20", "47B47", "47L25", "47L50" ], "keywords": [ "abstract harmonic analysis", "homological algebra", "locally compact group", "canonical operator space structure", "hochschild cohomology groups" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 12, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2002math......6041R" } } }