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THE COVERING NUMBERS OF SOME MYCIELSKI IDEALS MAY BE DIFFERENT

Part of: Set theory

Published online by Cambridge University Press:  30 January 2025

OTMAR SPINAS
OTMAR SPINAS*
Affiliation:
MATHEMATISCHES SEMINAR CHRISTIAN-ALBRECHTS-UNIVERSITÄT ZU KIEL HEINRICH-HECHT-PLATZ 6 KIEL 24118, GERMANY
*
Email: [email protected]
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Abstract

We show that in the Silver model the inequality $\mathrm {cov}(\mathfrak {C} _2) < \mathrm {cov}(\mathfrak {P}_2)$ holds true, where $\mathfrak {C}_2$ and $\mathfrak {P}_2$ are the two-dimensional Mycielski ideals.

Keywords

Mycielski idealstree idealscovering coefficientsSilver forcingSacks treeuniform tree

MSC classification

Primary: 03E17: Cardinal characteristics of the continuum 03E35: Consistency and independence results
Type
Article
Information
The Journal of Symbolic Logic , First View , pp. 1 - 26
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Copyright
© The Author(s), 2025. Published by Cambridge University Press on behalf of The Association for Symbolic Logic

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