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arXiv · 1709.04824

Spectra of uniformity

Yair Hayut·Asaf Karagila
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Abstract

We study some limitations and possible occurrences of uniform ultrafilters on ordinals without the axiom of choice. We prove an Easton-like theorem about the possible spectrum of successors of regular cardinals which carry uniform ultrafilters; we also show that this spectrum is not necessarily closed.

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Yair Hayut, Asaf Karagila. 2018-07-23. Spectra of uniformity. https://doi.org/10.14712/1213-7243.2019.008

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