The R ∞ Property for Abelian Groups
نویسنده
چکیده
It is well known there is no finitely generated abelian group which has the R∞ property. We will show that also many non-finitely generated abelian groups do not have the R∞ property, but this does not hold for all of them! In fact we construct an uncountable number of infinite countable abelian groups which do have the R∞ property. We also construct an abelian group such that the cardinality of the Reidemeister classes is uncountable for any automorphism of that group.
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