FINITELY PRESENTED INVERSE SEMIGROUPS WITH FINITELY MANY IDEMPOTENTS IN EACH -CLASS AND NON-HAUSDORFF UNIVERSAL GROUPOIDS

Abstract The complex algebra of an inverse semigroup with finitely many idempotents in each $\mathcal D$ -class is stably finite by a result of Munn. This can be proved fairly easily using $C^{*}$ -algebras for inverse semigroups satisfying this condition that have a Hausdorff universal groupoid, or...

Full description

Saved in:
Bibliographic Details
Published in:Journal of the Australian Mathematical Society (2001) 2024-06, Vol.116 (3), p.1-15
Main Authors: SILVA, PEDRO V., STEINBERG, BENJAMIN
Format: Article
Language:eng
Subjects:
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Abstract The complex algebra of an inverse semigroup with finitely many idempotents in each $\mathcal D$ -class is stably finite by a result of Munn. This can be proved fairly easily using $C^{*}$ -algebras for inverse semigroups satisfying this condition that have a Hausdorff universal groupoid, or more generally for direct limits of inverse semigroups satisfying this condition and having Hausdorff universal groupoids. It is not difficult to see that a finitely presented inverse semigroup with a non-Hausdorff universal groupoid cannot be a direct limit of inverse semigroups with Hausdorff universal groupoids. We construct here countably many nonisomorphic finitely presented inverse semigroups with finitely many idempotents in each $\mathcal D$ -class and non-Hausdorff universal groupoids. At this time, there is not a clear $C^{*}$ -algebraic technique to prove these inverse semigroups have stably finite complex algebras.
ISSN:1446-7887
1446-8107