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

Abstract

We show that there is a set of $2^{2^{\kappa }}$ ultrafilters incomparable in Rudin-Frolík order of $\beta \kappa \setminus \kappa$, where $\kappa$ is regular, for which no subset with more than one element has an infimum.

arXiv commentarXiv admin note: substantial text overlap with arXiv:2304.00097, arXiv:2304.01398