A note on special subsets of the Rudin-Frolík order for regulars

2023/03/28 by Joanna Jureczko, Jureczko, Joanna
Engineering · Mathematics · #FOS: Mathematics #Graph theory and applications #Logic (math.LO) #Rings, Modules, and Algebras #graph theory and CDMA systems

paper · pdf · doi:10.48550/arxiv.2304.02143

openalex publication_date 2023/03/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We show that there is a set of 2^2κ ultrafilters incomparable in Rudin-Frolík order of βκ∖ κ, where κ is regular, for which no subset with more than one element has an infimum.

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