{ "id": "0710.3521", "version": "v1", "published": "2007-10-18T14:30:30.000Z", "updated": "2007-10-18T14:30:30.000Z", "title": "$C^*-$crossed product of groupoid actions on categories", "authors": [ "Han Li" ], "comment": "14 pages", "categories": [ "math.OA", "math.CT" ], "abstract": "Suppose that $G$ is a groupoid acting on a small category $H$ in the sense of \\cite[Definition 4]{NOT} and $H\\times_\\alpha G$ is the resulting semi-direct product category (as in \\cite[Proposition 8]{NOT}). We show that there exists a subcategory $H_r \\subseteq H$ satisfying some nice property called ``regularity'' such that $H_r \\times_\\alpha G = H\\times_\\alpha G$. Moreover, we show that there exists a so-called ``quasi action'' (see Definition \\ref{quasi}) $\\beta$ of $G$ on $C^*(H_r)$ (where $C^*(H_r)$ is the semigroupoid $C^*$-algebra as defined in \\cite{EXE}) such that $C^*(H_r\\times_\\alpha G) = C^*(H_r)\\times_\\beta G$ (where the crossed product for $\\beta$ is as defined in Definition \\ref{cross}).", "revisions": [ { "version": "v1", "updated": "2007-10-18T14:30:30.000Z" } ], "analyses": { "subjects": [ "46L05", "18B40" ], "keywords": [ "crossed product", "groupoid actions", "resulting semi-direct product category", "quasi action", "nice property" ], "note": { "typesetting": "TeX", "pages": 14, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2007arXiv0710.3521L" } } }