Twisted cyclic theory and an index theory for the gauge invariant KMS state on Cuntz algebras
| dc.creator | Carey, A. L. | |
| dc.creator | Phillips, J. | |
| dc.creator | Rennie, A. | |
| dc.date | 2008-01-30 | |
| dc.date | 2008-02-29 | |
| dc.date.accessioned | 2026-07-07T09:23:42Z | |
| dc.date.available | 2026-07-07T09:23:42Z | |
| dc.description | This paper presents, by example, an index theory appropriate to algebras without trace. Whilst we work exclusively with the Cuntz algebras the exposition is designed to indicate how to develop a general theory. Our main result is an index theorem (formulated in terms of spectral flow) using a twisted cyclic cocycle where the twisting comes from the modular automorphism group for the canonical gauge action on the Cuntz algebra. We introduce a modified $K_1$-group of the Cuntz algebra so as to pair with this twisted cocycle. As a corollary we obtain a noncommutative geometry interpretation for Araki's notion of relative entropy in this example. We also note the connection of this example to the theory of noncommutative manifolds. | |
| dc.description | 27 pages, minor corrections | |
| dc.identifier | https://arxiv.org/abs/0801.4605 | |
| dc.identifier | http://arxiv.org/abs/0801.4605 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/155830 | |
| dc.subject | K-Theory and Homology | |
| dc.subject | Operator Algebras | |
| dc.subject | 46L80 | |
| dc.title | Twisted cyclic theory and an index theory for the gauge invariant KMS state on Cuntz algebras | |
| dc.type | text |