Models of set theory in which separation theorem fails

Vladimir Kanovei; Vassily Lyubetsky

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arXiv · 1905.11241

Models of set theory in which separation theorem fails

Vladimir Kanovei·Vassily Lyubetsky

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Abstract

We make use of a finite support product of the Jensen minimal forcing to define a model of set theory in which the separation theorem fails for projective classes $\mathbf\Sigma^1_n$ and $\mathbf\Pi^1_n$, for a given $n\ge3$.

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Vladimir Kanovei, Vassily Lyubetsky. 2019-05-24. Models of set theory in which separation theorem fails. https://arxiv.org/abs/1905.11241

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