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arXiv · 2302.05539

Stable ordered-union versus selective ultrafilters

Dilip Raghavan·Juris Steprans
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Abstract

It will be shown to be consistent that there are at least two non-isomorphic selective ultrafilters, but no stable ordered-union ultrafilters. This answers a question of Blass from his 1987 paper which introduced the concept of a stable ordered-union ultrafilter.

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Dilip Raghavan, Juris Steprans. 2023-02-10. Stable ordered-union versus selective ultrafilters. https://arxiv.org/abs/2302.05539

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