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arXiv · 1408.3901

A countable definable set of reals containing no definable elements

Vladimir Kanovei·Vassily Lyubetsky
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Abstract

We make use of a finite support product of Jensen forcing to define a model in which there is a countable non-empty lightface $\Pi^1_2$ set of reals containing no ordinal-definable real.

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BibTeXRIS

Vladimir Kanovei, Vassily Lyubetsky. 2014-08-18. A countable definable set of reals containing no definable elements. https://doi.org/10.1134/s0001434617090048

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