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arXiv · 1510.02141

Separating the Fan Theorem and Its Weakenings

Robert S. Lubarsky·Hannes Diener
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Abstract

Varieties of the Fan Theorem have recently been developed in reverse constructive mathematics, corresponding to different continuity principles. They form a natural implicational hierarchy. Some of the implications have been shown to be strict, others strict in a weak context, and yet others not at all, using disparate techniques. Here we present a family of related Kripke models which separates all of the as yet identified fan theorems.

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BibTeXRIS

Robert S. Lubarsky, Hannes Diener. 2015-10-07. Separating the Fan Theorem and Its Weakenings. https://doi.org/10.1017/jsl.2014.9

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