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arXiv · 2609.34813

Some étale groupoids as groupoids of fractions

Mark V. Lawson
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Abstract

Given a monoid that can be embedded in a group and that acts partially on a set, we show that under certain conditions the category associated with the partial action has a groupoid of fractions. By imposing some topological conditions on the action, we show that the groupoid is actually étale. This étale groupoid arises naturally in $C^{\ast}$-algebra theory.

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Mark V. Lawson. 2026-09-28. Some étale groupoids as groupoids of fractions. https://arxiv.org/abs/2609.34813

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