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arXiv · 1610.03985

Fodor's lemma can fail everywhere

Asaf Karagila
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Abstract

We show that it is equiconsistent with $\mathsf{ZF}$ that Fodor's lemma fails everywhere, and furthermore that the club filter on every regular cardinal is not even $σ$-complete. Moreover, these failures can be controlled in a very precise manner.

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Asaf Karagila. 2017-05-31. Fodor's lemma can fail everywhere. https://doi.org/10.1007/s10474-017-0768-5

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