Almost disjoint pure subgroups of the Baer-Specker group

Oren Kolman, Saharon Shelah

发表信息：: Abelian groups and modules (Dublin, 1998), Trends in Mathematics, 225-230, Birkhauser, Basel, 1999

英文摘要：

We prove in ZFC that the Baer-Specker group Z^omega has 2^{aleph_1} non-free pure subgroups of cardinality aleph_1 which are almost disjoint: there is no non-free subgroup embeddable in any pair.

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