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Regulating hulls of almost completely decomposable groups

Part of: Abelian groups

Published online by Cambridge University Press:  09 April 2009

A. Mader  and
C. Vinsonhaler
A. Mader
Affiliation:
University of HawaiiHonolulu, HI 96822, USA
C. Vinsonhaler
Affiliation:
University of ConnecticutStorrs, CT 06269, USA
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Abstract

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This note investigates torsion-free abelian groups G of finite rank which embed, as subgroups of finite index, in a finite direct sum C of subgroups of the additive group of rational numbers. Specifically, we examine the relationship between G and C when the index of G in C is minimal. Some properties of Warfield duality are developed and used (in the case that G is locally free) to relate our results to earlier ones by Burkhardt and Lady.

MSC classification

Secondary: 20K15: Torsion-free groups, finite rank
Type
Research Article
Information
Journal of the Australian Mathematical Society , Volume 54 , Issue 2 , April 1993 , pp. 143 - 155
Copyright
Copyright © Australian Mathematical Society 1993

References

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