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The minimal cofinality of an ultrapower of ω and the cofinality of the symmetric group can be larger than b+

Published online by Cambridge University Press:  12 March 2014

Heike Mildenberger  and
Saharon Shelah
Heike Mildenberger
Affiliation:
Abteilung für Mathematische Logik, Mathematisches Institut, Universität Freiburg, Eckerstr. 1, 79104 Freiburg im Breisgau, Germany, E-mail: heike.mildenberger@math.uni-freiburg.de
Saharon Shelah
Affiliation:
Einstein Institute of Mathematics, The Hebrew University, Edmond Safra Campus Givat Ram, Jerusalem 91904, Israel, E-mail: shelah@math.huji.ac.il
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Abstract

We prove the statement in the title.

Keywords

forcing techniqueminimum cofinality of an ultrapowercofinality of the symmetric group

Information

Type
Research Article
Information
The Journal of Symbolic Logic , Volume 76 , Issue 4 , December 2011 , pp. 1322 - 1340
Copyright
Copyright © Association for Symbolic Logic 2011

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References

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