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arXiv · 1708.00642

A separation result for countable unions of Borel rectangles

Dominique Lecomte
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Abstract

We provide dichotomy results characterizing when two disjoint analytic binary relations can be separated by a countable union of ${\bfΣ}^0_1 \!\times\! {\bfΣ}^0_ξ$ sets, or by a ${\bfΠ}^0_1 \!\times\! {\bfΠ}^0_ξ$ set.

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BibTeXRIS

Dominique Lecomte. 2017-08-02. A separation result for countable unions of Borel rectangles. https://doi.org/10.1017/jsl.2019.13

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