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arXiv · 1408.6642

A definable $\mathsf E_0$-class containing no definable elements

Vladimir Kanovei·Vassily Lyubetsky
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Abstract

A generic extension $L[x]$ of $L$ by a real $x$ is defined, in which the $\mathsf E_0$-class of $x$ is a lightface $\Pi^1_2$ set containing no ordinal-definable reals.

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BibTeXRIS

Vladimir Kanovei, Vassily Lyubetsky. 2014-08-28. A definable $\mathsf E_0$-class containing no definable elements. https://doi.org/10.1007/s00153-015-0436-9

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