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There may be infinitely many near-coherence classes under u < ∂

Published online by Cambridge University Press:  12 March 2014

Heike Mildenberger
Heike Mildenberger*
Affiliation:
Universität Wien, Kurt Gödel Research Center for Mathematical Logic, Währinger Str. 25 1090 Vienna, Austria. E-Mail: Heike@Logic.Univie.Ac.At
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Abstract

We show that in the models of u < ∂ from [14] there are infinitely many near-coherence classes of ultrafilters, thus answering Banakh's and Blass' Question 30 of [3] negatively. By an unpublished result of Canjar, there are at least two classes in these models.

Type
Research Article
Information
The Journal of Symbolic Logic , Volume 72 , Issue 4 , December 2007 , pp. 1228 - 1238
Copyright
Copyright © Association for Symbolic Logic 2007

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