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There may be no Hausdorff ultrafilters

Tomek Bartoszynski·Saharon Shelah
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Abstract

An ultrafilter U is Hausdorff if for any two functions f,g mapping N to N, f(U)=g(U) iff f(n)=g(n) for n in some X in U. We will show that it is consistent that there are no Hausdorff ultrafilters.

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BibTeXRIS

Tomek Bartoszynski, Saharon Shelah. 2003-11-05. There may be no Hausdorff ultrafilters. https://arxiv.org/abs/math/0311064

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