# Sh:826

• Bartoszyński, T., & Shelah, S. (2008). On the density of Hausdorff ultrafilters. In Logic Colloquium 2004, Vol. 29, Assoc. Symbol. Logic, Chicago, IL, pp. 18–32.
• Abstract:
An ultrafilter U is Hausdorff if for any two functions f,g \in \omega^\omega, f(U)=g(U) iff f \restriction X=g\restriction X for some X \in U. We will show that the statement that Hausdorff ultrafilters are dense in the Rudin-Keisler order is independent of ZFC
• Version 2006-07-13_11 (12p) published version (15p)
Bib entry
@incollection{Sh:826,
author = {Bartoszy{\'n}ski, Tomek and Shelah, Saharon},
title = {{On the density of Hausdorff ultrafilters}},
booktitle = {{Logic Colloquium 2004}},
series = {Lect. Notes Log.},
volume = {29},
year = {2008},
pages = {18--32},
publisher = {Assoc. Symbol. Logic, Chicago, IL},
mrnumber = {2401857},
mrclass = {03E05 (03E35 54A25)},
note = {\href{https://arxiv.org/abs/math/0311064}{arXiv: math/0311064}},
arxiv_number = {math/0311064}
}