Hostname: page-component-848d4c4894-sjtt6 Total loading time: 0 Render date: 2024-06-24T00:25:33.809Z Has data issue: false hasContentIssue false

Subquotients of Hecke C*-algebras

Published online by Cambridge University Press:  04 August 2005

NATHAN BROWNLOWE
Affiliation:
School of Mathematical and Physical Sciences, University of Newcastle, NSW 2308, Australia (e-mail: Nathan.Brownlowe@studentmail.newcastle.edu.au, iain@frey.newcastle.edu.au)
NADIA S. LARSEN
Affiliation:
Department of Mathematics, Institute for Mathematical Sciences, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark (e-mail: nadiasl@math.uio.no) Department of Mathematics, University of Oslo, P.O. Box 1053, Blindern, N-0316 Oslo, Norway
IAN F. PUTNAM
Affiliation:
Department of Mathematics and Statistics, University of Victoria, British Columbia V8W 3P4, Canada (e-mail: putnam@math.uvic.ca)
IAIN RAEBURN
Affiliation:
School of Mathematical and Physical Sciences, University of Newcastle, NSW 2308, Australia (e-mail: Nathan.Brownlowe@studentmail.newcastle.edu.au, iain@frey.newcastle.edu.au)

Abstract

We realize the Hecke C*-algebra $\mathcal{C}_{\mathbb{Q}}$ of Bost and Connes as a direct limit of Hecke C*-algebras which are semigroup crossed products by $\mathbb{N}^F$, for F a finite set of primes. For each approximating Hecke C*-algebra we describe a composition series of ideals. In all cases there is a large type I ideal and a commutative quotient, and the intermediate subquotients are direct sums of simple C*-algebras. We can describe the simple summands as ordinary crossed products by actions of $\mathbb{Z}^S$ for S a finite set of primes. When $\vert S\vert =1$, these actions are odometers and the crossed products are Bunce–Deddens algebras; when $\vert S\vert >1$, the actions are an apparently new class of higher-rank odometer actions, and the crossed products are an apparently new class of classifiable AT-algebras.

Type
Research Article
Copyright
2005 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)