Finitely presented inverse semigroups with finitely many idempotents in each $\mathcal D$-class and non-Hausdorff universal groupoids
Abstract
The complex algebra of an inverse semigroup with finitely many idempotents in each -class is stably finite by a result of Munn. This can be proved fairly easily using -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 non-isomorphic finitely presented inverse semigroups with finitely many idempotents in each -class and non-Hausdorff universal groupoids. At this time there is not a clear -algebraic technique to prove these inverse semigroups have stably finite complex algebras.
Keywords
Cite
@article{arxiv.2207.11206,
title = {Finitely presented inverse semigroups with finitely many idempotents in each $\mathcal D$-class and non-Hausdorff universal groupoids},
author = {Pedro V. Silva and Benjamin Steinberg},
journal= {arXiv preprint arXiv:2207.11206},
year = {2022}
}