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A counterexample regarding an equivalence relation on a product space

Part of: Set theory

Published online by Cambridge University Press:  16 April 2025

Assaf Shani Open the ORCID record for Assaf Shani [Opens in a new window]
Assaf Shani*
Affiliation:
Department of Mathematics and Statistics, Concordia University, Montreal, QC H3G 1M8, Canada URL: https://sites.google.com/view/assaf-shani/
*
e-mail: assaf.shani@concordia.ca
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Abstract

We present a counterexample to [Kan08, Conjecture 14.1.6], regarding Borel equivalence relations on product spaces.

Keywords

Borel equivalence relationsBorel reducibilityFriedman-Stanley jump

MSC classification

Primary: 03E15: Descriptive set theory

Information

Type
Article
Information
Canadian Mathematical Bulletin , Volume 68 , Issue 4 , December 2025 , pp. 1262 - 1266
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Copyright
© The Author(s), 2025. Published by Cambridge University Press on behalf of Canadian Mathematical Society

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Footnotes

Research partially supported by NSF grant DMS-2246746 and NSERC grant RGPIN-2024-05827.

References

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