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arXiv · 1101.5660

Lifting up the proof theory to the countables : Zermelo-Fraenkel set theory

Toshiyasu Arai
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Abstract

We describe the countable ordinals in terms of iterations of Mostowski collapsings. This gives a proof-theoretic bound of definable countable ordinals in the Zermelo-Fraenkel's set theory ZF.

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BibTeXRIS

Toshiyasu Arai. 2011-01-29. Lifting up the proof theory to the countables : Zermelo-Fraenkel set theory. https://arxiv.org/abs/1101.5660

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