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arXiv · 2409.16445

Hyper-hyperfiniteness and complexity

Joshua Frisch·Forte Shinko·Zoltan Vidnyanszky
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Abstract

We show that if there exists a countable Borel equivalence relation which is hyper-hyperfinite but not hyperfinite then the complexity of hyperfinite countable Borel equivalence relations is as high as possible, namely, $\Sigma^1_2$-complete.

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Joshua Frisch, Forte Shinko, Zoltan Vidnyanszky. 2024-09-24. Hyper-hyperfiniteness and complexity. https://arxiv.org/abs/2409.16445

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