Chern character for twisted K-theory of orbifolds
Abstract
For an orbifold X and , we introduce the twisted cohomology and prove that the Connes-Chern character establishes an isomorphism between the twisted K-groups and twisted cohomology . This theorem, on the one hand, generalizes a classical result of Baum-Connes, Brylinski-Nistor, and others, that if X is an orbifold then the Chern character establishes an isomorphism between the K-groups of X tensored with C, and the compactly-supported cohomology of the inertia orbifold. On the other hand, it also generalizes a recent result of Adem-Ruan regarding the Chern character isomorphism of twisted orbifold K-theory when the orbifold is a global quotient by a finite group and the twist is a special torsion class, as well as Mathai-Stevenson's theorem regarding the Chern character isomorphism of twisted K-theory of a compact manifold.
Cite
@article{arxiv.math/0505267,
title = {Chern character for twisted K-theory of orbifolds},
author = {Jean-Louis Tu and Ping Xu},
journal= {arXiv preprint arXiv:math/0505267},
year = {2007}
}
Comments
26 pages. To appear in Advances in Mathematics