Topology of character varieties of Abelian groups

Autor: Florentino, C., Lawton, S.
Rok vydání: 2013
Předmět:
Zdroj: Topology and its Applications, Volume 173, 15 August 2014, Pages 32-58
Druh dokumentu: Working Paper
DOI: 10.1016/j.topol.2014.05.009
Popis: 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.
Comment: 33 pages; version 3: few small changes, one error corrected, one or two additional references; to appear in Topology and its Applications
Databáze: arXiv