# Sh:594

• Shelah, S. (1998). There may be no nowhere dense ultrafilter. In Logic Colloquium ’95 (Haifa), Vol. 11, Springer, Berlin, pp. 305–324.
• Abstract:
We show the consistency of ZFC + "there is no NWD-ultrafilter on \omega", which means: for every non principle ultrafilter D on the set of natural numbers, there is a function f from the set of natural numbers to the reals, such that for some nowhere dense set A of reals, the set \{n: f(n)\in A\} is not in D. This answers a question of van Douwen, which was put in more general context by Baumgartner
• published version (12p)
Bib entry
@incollection{Sh:594,
author = {Shelah, Saharon},
title = {{There may be no nowhere dense ultrafilter}},
booktitle = {{Logic Colloquium '95 (Haifa)}},
series = {Lecture Notes Logic},
volume = {11},
year = {1998},
pages = {305--324},
publisher = {Springer, Berlin},
mrnumber = {1690694},
mrclass = {03E05 (03E35)},
doi = {10.1007/978-3-662-22108-2_17},
note = {\href{https://arxiv.org/abs/math/9611221}{arXiv: math/9611221}},
arxiv_number = {math/9611221}
}