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arXiv · 1801.02517

On the cofinality of the splitting number

Alan Dow·Saharon Shelah
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Abstract

The splitting number can be singular. The key method is to construct a forcing poset with finite support matrix iterations of ccc posets introduced by Blass and the second author "Ultrafilters with small generating sets", Israel J. Math., 65, (1989)

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Alan Dow, Saharon Shelah. 2018-01-08. On the cofinality of the splitting number. https://arxiv.org/abs/1801.02517

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