{ "id": "1202.0987", "version": "v3", "published": "2012-02-05T18:19:39.000Z", "updated": "2015-09-17T14:11:12.000Z", "title": "The $ΞΎ$-stability on the affine grassmannian", "authors": [ "Zongbin Chen" ], "comment": "23 pages, Published version on Mathematische Zeitschrift", "categories": [ "math.AG", "math.RT" ], "abstract": "We introduce a notion of $\\xi$-stability on the affine grassmannian $\\xx$ for the classical groups, this is the local version of the $\\xi$-stability on the moduli space of Higgs bundles on a curve introduced by Chaudouard and Laumon. We prove that the quotient $\\xx^{\\xi}/T$ of the stable part $\\xx^{\\xi}$ by the maximal torus $T$ exists as an ind-$k$-scheme, and we introduce a reduction process analogous to the Harder-Narasimhan reduction for vector bundles. For the group $\\mathrm{SL}_{d}$, we calculate the Poincar\\'e series of the quotient $\\xx^{\\xi}/T$.", "revisions": [ { "version": "v2", "updated": "2014-05-06T14:07:19.000Z", "comment": "22 pages, 1 figure", "journal": null, "doi": null }, { "version": "v3", "updated": "2015-09-17T14:11:12.000Z" } ], "analyses": { "subjects": [ "22E67" ], "keywords": [ "affine grassmannian", "poincare series", "vector bundles", "local version", "harder-narasimhan reduction" ], "note": { "typesetting": "TeX", "pages": 23, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1202.0987C" } } }