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arXiv · 1510.02147

Realizability Models Separating Various Fan Theorems

Robert S. Lubarsky·Michael Rathjen
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Abstract

We develop a realizability model in which the realizers are the reals not just Turing computable in a fixed real but rather the reals in a countable ideal of Turing degrees. This is then applied to prove several separation results involving variants of the Fan Theorem.

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Robert S. Lubarsky, Michael Rathjen. 2015-10-07. Realizability Models Separating Various Fan Theorems. https://arxiv.org/abs/1510.02147

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