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A note on products of homogeneous torsion free abelian groups [PDF]

Proceedings of the American Mathematical Society, 1969
In his book on abelian groups, L. Fuchs remarks [1, p. 173] that a direct product of torsion free groups of rank one and the same type r is a homogeneous torsion free group of type r. It is easy to give an example to show that this is not the case. Moreover, the example suggests the correct statement concerning the type set of an infinite product of ...
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KULIKOV'S PROBLEM ON UNIVERSAL TORSION-FREE ABELIAN GROUPS

Journal of the London Mathematical Society, 2003
Let T be an abelian group and lambda an uncountable regular cardinal. We consider the question of whether there is a lambda-universal group G^* among all torsion-free abelian groups G of cardinality less than or equal to lambda satisfying Ext(G,T)=0.
Shelah, Saharon, Strüngmann, Lutz
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On the indecomposability of torsion-free abelian groups [PDF]

Proceedings of the American Mathematical Society, 1965
1. We consider the following question posed by E. Weinberg [4, ?5.2]: Does there exist a torsion-free abelian group of cardinality greater than the continuum (K) with the property that each pure subgroup is (directly) indecomposable? In ?2 we answer this question negatively for a large class of groups which contains, most notably, the class of ...
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On the Abelianization of a Torsion Free Crystallographic Group

Jurnal Teknologi, 2014
A torsion free crystallographic group, which is also known as a Bieberbach group is a generalization of free abelian groups. It is an extension of a lattice group by a finite point group. The study of n-dimensional crystallographic group had been done by many researchers over a hundred years ago.
Mohd. Idrus, Nor'ashiqin +3 more
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Symmetry TFTs from String Theory. [PDF]