## Notre Dame Journal of Formal Logic

### On the Spectrum of Characters of Ultrafilters

#### Abstract

We show that the character spectrum $\operatorname{Sp}_{\chi}(\lambda)$ (for a singular cardinal $\lambda$ of countable cofinality) may include any prescribed set of regular cardinals between $\lambda$ and $2^{\lambda}$.

#### Article information

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

Dates
Accepted: 5 January 2016
First available in Project Euclid: 19 June 2018

https://projecteuclid.org/euclid.ndjfl/1529373704

Digital Object Identifier
doi:10.1215/00294527-2018-0006

Mathematical Reviews number (MathSciNet)
MR3832086

Zentralblatt MATH identifier
06939325

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

#### Citation

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. https://projecteuclid.org/euclid.ndjfl/1529373704

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