Journal of Symbolic Logic

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

Heike Mildenberger and Saharon Shelah

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Abstract

We prove the statement in the title.

Article information

Source
J. Symbolic Logic, Volume 76, Issue 4 (2011), 1322-1340.

Dates
First available in Project Euclid: 11 October 2011

Permanent link to this document
https://projecteuclid.org/euclid.jsl/1318338852

Digital Object Identifier
doi:10.2178/jsl/1318338852

Mathematical Reviews number (MathSciNet)
MR2895398

Zentralblatt MATH identifier
1271.03067

Subjects
Primary: 03E05: Other combinatorial set theory 03E17: Cardinal characteristics of the continuum 03E35: Consistency and independence results

Keywords
forcing technique minimum cofinality of an ultrapower cofinality of the symmetric group

Citation

Mildenberger, Heike; Shelah, Saharon. The minimal cofinality of an ultrapower of ω and the cofinality of the symmetric groupcan be larger than 𝔟 +. J. Symbolic Logic 76 (2011), no. 4, 1322--1340. doi:10.2178/jsl/1318338852. https://projecteuclid.org/euclid.jsl/1318338852


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