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A separation result for countable unions of Borel rectangles

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 نشر من قبل Dominique Lecomte
 تاريخ النشر 2017
  مجال البحث
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 تأليف Dominique Lecomte




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

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