{ "id": "0803.0252", "version": "v1", "published": "2008-03-03T15:08:19.000Z", "updated": "2008-03-03T15:08:19.000Z", "title": "Secondary multiplication in Tate cohomology of certain p-groups", "authors": [ "Martin Langer" ], "comment": "35 pages", "categories": [ "math.AT", "math.GR" ], "abstract": "Let k be a field and let G be a finite group. By a theorem of D.Benson, H.Krause and S.Schwede, there is a canonical element in the Hochschild cohomology of the Tate cohomology HH^{3,-1} H*G with the following property: Given any graded H*G-module X, the image of the canonical element in Ext^{3,-1}(X,X) is zero if and only if X is isomorphic to a direct summand of H*(G,M) for some kG-module M. We investigate this canonical element in certain special cases, namely that of (finite) abelian p-groups and the quaternion group. In case of non-triviality of the canonical element, we also give examples of non-realizable modules X.", "revisions": [ { "version": "v1", "updated": "2008-03-03T15:08:19.000Z" } ], "analyses": { "subjects": [ "20J06", "55S35" ], "keywords": [ "tate cohomology", "secondary multiplication", "canonical element", "finite group", "quaternion group" ], "note": { "typesetting": "TeX", "pages": 35, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2008arXiv0803.0252L" } } }