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arXiv · 2003.01272

Characterizing the spectra of cardinalities of branches of Kurepa trees

Márk Poór·Saharon Shelah
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Abstract

We give a complete characterization of the sets of cardinals that in a suitable forcing extension can be the Kurepa spectrum, that is, the set of cardinalities of branches of Kurepa trees. This answers a question of the first named author.

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Márk Poór, Saharon Shelah. 2020-03-03. Characterizing the spectra of cardinalities of branches of Kurepa trees. https://doi.org/10.2140/pjm.2021.311.423

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