A homological characterization of AF groupoids

Abstract An ample groupoid is said to be AF if it is a directed union of compact open principal subgroupoids. In this paper, we provide a complete homological characterization of these groupoids. Specifically, we prove that an ample groupoid is AF if and only if it has homological dimension zero. More generally, we characterize groupoids of homological dimension zero over a unital ring .

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Publication Details

Journal
Bulletin of the London Mathematical Society
Published
2026-10-28
DOI
https://doi.org/10.1112/blms.70541
Primary Topic
Advanced Operator Algebra Research
Type
article
Field-Weighted Citation Impact
0.00

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article

A homological characterization of AF groupoids

Benjamin Steinberg
3 links
Bulletin of the London Mathematical Society
Advanced Operator Algebra Research
article

A homological characterization of AF groupoids

Benjamin Steinberg
article en

Abstract

Abstract An ample groupoid is said to be AF if it is a directed union of compact open principal subgroupoids. In this paper, we provide a complete homological characterization of these groupoids. Specifically, we prove that an ample groupoid is AF if and only if it has homological dimension zero. More generally, we characterize groupoids of homological dimension zero over a unital ring .

Bulletin of the London Mathematical SocietyVol. 58(11)
City College of New York (US)
National Science Foundation, Marsden Fund
Openalex Percentile: Top 54%
Advanced Operator Algebra Research
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A homological characterization of AF groupoids — Benjamin Steinberg · Bulletin of the London Mathematical Society (2026) | TGRS Research Map | TGRS