Ultrafilters without immediate predecessors in Rudin-Frolik order for regulars

2023/03/28 by Jureczko, Joanna
#FOS: Mathematics #Logic (math.LO)

paper · doi:10.48550/arxiv.2305.02794

Abstract

The aim of this paper is to construct ultrafilters without immediate predecessors in the Rudin-Frolik order in βκ∖ κ, where κ is a regular cardinal. This generalizes the problem posed by Peter Simon more than 40 years ago.

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