Characterizing Subgroups of Compact Abelian Groups

Dikran Dikranjan; Kenneth Kunen

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Characterizing Subgroups of Compact Abelian Groups

Dikran Dikranjan·Kenneth Kunen

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Abstract

We prove that every countable subgroup of a compact metrizable abelian group has a characterizing set. As an application, we answer several questions on maximally almost periodic (MAP) groups and give a characterization of the class of (necessarily MAP) abelian topological groups whose Bohr topology has countable pseudocharacter.

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Dikran Dikranjan, Kenneth Kunen. 2004-12-16. Characterizing Subgroups of Compact Abelian Groups. https://arxiv.org/abs/math/0412327

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