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arXiv · 2410.15147

Measured groupoids beyond equivalence relations and group actions

Soham Chakraborty
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Abstract

We construct the first examples of genuine ergodic discrete measured groupoids that are not isomorphic to any equivalence relation or transformation groupoid. We use a construction due to B.H. Neumann of an uncountable family of pairwise non-isomorphic 2-generated groups for our result.

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Soham Chakraborty. 2024-10-19. Measured groupoids beyond equivalence relations and group actions. https://arxiv.org/abs/2410.15147

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