{ "id": "1301.7616", "version": "v3", "published": "2013-01-31T13:57:13.000Z", "updated": "2014-05-12T20:07:26.000Z", "title": "Topology of character varieties of Abelian groups", "authors": [ "C. Florentino", "S. Lawton" ], "comment": "33 pages; version 3: few small changes, one error corrected, one or two additional references; to appear in Topology and its Applications", "journal": "Topology and its Applications, Volume 173, 15 August 2014, Pages 32-58", "doi": "10.1016/j.topol.2014.05.009", "categories": [ "math.AG", "math.GT", "math.RT" ], "abstract": "Let G be a complex reductive algebraic group (not necessarily connected), let K be a maximal compact subgroup, and let A be a finitely generated Abelian group. We prove that the conjugation orbit space Hom(A,K)/K is a strong deformation retract of the GIT quotient space Hom(A,G)//G. As a corollary, we determine necessary and sufficient conditions for the character variety Hom(A,G)//G to be irreducible when G is connected and semisimple. For a general connected reductive G, analogous conditions are found to be sufficient for irreducibility, when A is free abelian.", "revisions": [ { "version": "v3", "updated": "2014-05-12T20:07:26.000Z" } ], "analyses": { "subjects": [ "14L30", "14P25", "14L17", "14L24", "22E46" ], "keywords": [ "conjugation orbit space hom", "git quotient space hom", "maximal compact subgroup", "character variety hom", "complex reductive algebraic group" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 33, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2013arXiv1301.7616F" } } }