Notre Dame Journal of Formal Logic

On the Spectrum of Characters of Ultrafilters

Shimon Garti, Menachem Magidor, and Saharon Shelah

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We show that the character spectrum Spχ(λ) (for a singular cardinal λ of countable cofinality) may include any prescribed set of regular cardinals between λ and 2λ.

Article information

Notre Dame J. Formal Logic, Volume 59, Number 3 (2018), 371-379.

Received: 25 November 2014
Accepted: 5 January 2016
First available in Project Euclid: 19 June 2018

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 03E05: Other combinatorial set theory
Secondary: 03E55: Large cardinals

supercompactness Prikry forcing ultrafilter number


Garti, Shimon; Magidor, Menachem; Shelah, Saharon. On the Spectrum of Characters of Ultrafilters. Notre Dame J. Formal Logic 59 (2018), no. 3, 371--379. doi:10.1215/00294527-2018-0006.

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