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arXiv · 1402.5616

Mad Spectra

Saharon Shelah·Otmar Spinas
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Abstract

The mad spectrum is the set of all cardinalities of infinite maximal almost disjoint families on omega. We treat the problem to characterize those sets A which, in some forcing extension of the universe, can be the mad spectrum. We solve this problem to some extent. What remains open is the possible values of min(A) and max(A).

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Saharon Shelah, Otmar Spinas. 2014-02-23. Mad Spectra. https://arxiv.org/abs/1402.5616

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