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Hereditarily separable groups and monochromatic uniformization

Paul C. Eklof·Alan H. Mekler·Saharon Shelah
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Abstract

We give a combinatorial equivalent to the existence of a non-free hereditarily separable group of cardinality aleph_1. This can be used, together with a known combinatorial equivalent of the existence of a non-free Whitehead group, to prove that it is consistent that every Whitehead group is free but not every hereditarily separable group is free. We also show that the fact that Z is a p.i.d. with infinitely many primes is essential for this result.

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BibTeXRIS

Paul C. Eklof, Alan H. Mekler, Saharon Shelah. 2004-06-27. Hereditarily separable groups and monochromatic uniformization. https://arxiv.org/abs/math/0406552

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