Abstract
In this work we show how endomorphisms of certain pure subgroups of the Baer–Specker group can be extended to endomorphisms of the whole group. This allows us to establish the existence of a large family of essentially indecomposable slender groups with prescribed endomorphism rings. The extension technique is then applied to show that the Baer–Specker group is a countably-free weak Crawley group which is not a Crawley group.
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Goldsmith, B., Karimi, F. On Pure Subgroups of the Baer–Specker Group and Weak Crawley Groups. Results. Math. 64, 105–112 (2013). https://doi.org/10.1007/s00025-012-0300-8
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DOI: https://doi.org/10.1007/s00025-012-0300-8