Deformations of Fell bundles and twisted graph algebras

作者:Raeburn Iain*
来源:Mathematical Proceedings of the Cambridge Philosophical Society, 2016, 161(3): 535-558.
DOI:10.1017/S0305004116000359

摘要

We consider Fell bundles over discrete groups, and the C*-algebra which is universal for representations of the bundle. We define deformations of Fell bundles, which are new Fell bundles with the same underlying Banach bundle but with the multiplication deformed by a two-cocycle on the group. Every graph algebra can be viewed as the C*-algebra of a Fell bundle, and there are many cocycles of interest with which to deform them. We thus obtain many of the twisted graph algebras of Kumjian, Pask and Sims. We demonstate the utility of our approach to these twisted graph algebras by proving that the deformations associated to different cocycles can be assembled as the fibres of a C*-bundle.

  • 出版日期2016-11