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arXiv · 1410.2537

Counterexamples to countable-section $\varPi^1_2$ uniformization and $\varPi^1_3$ separation

Vladimir Kanovei·Vassily Lyubetsky
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Abstract

We make use of a finite support product of the Jensen minimal $\varPi^1_2$ singleton forcing to define a model in which $\varPi^1_2$ Uniformization fails for a set with countable cross-sections. We also define appropriate submodels of the same model in which Separation fails for $\varPi^1_3$.

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Vladimir Kanovei, Vassily Lyubetsky. 2014-10-09. Counterexamples to countable-section $\varPi^1_2$ uniformization and $\varPi^1_3$ separation. https://doi.org/10.1016/j.apal.2015.12.002

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