Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-26T00:45:13.532Z Has data issue: false hasContentIssue false

Abelian Groups in Which Every α-Pure Subgroup is β-Pure

Published online by Cambridge University Press:  20 November 2018

J. Douglas Moore
Affiliation:
Arizona State University, Tempe, Arizona
Edwin J. Hewett
Affiliation:
Arizona State University, Tempe, Arizona
Rights & Permissions [Opens in a new window]

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The determination of the abelian groups in which every neat subgroup is pure is a relatively routine exercise (see [6]). There are numerous problems of this type; for example, the determination of the groups in which every pure subgroup is isotype or the groups in which every subgroup is isotype. These are all special cases of the general problem of determining the abelian groups in which every α-pure subgroup is β-pure for arbitrary ordinal numbers α and β. The solution of this general problem is the object of this paper.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1973

References

1. Fuchs, L., Abelian groups (Hungarian Academy of Sciences, Budapest, 1958).Google Scholar
2. Fuchs, L., Infinite abelian groups. Vol. 1 (Academic Press, New York, 1970).Google Scholar
3. Fuchs, L., Kertész, A., and Szele, T., Abelian groups in which every serving subgroup is a direct summand, Publ. Math. Debrecen 3 (1953), 95105.Google Scholar
4. Irwin, J. M. and Walker, E. A., On isotype subgroups of abelian groups, Bull. Soc. Math. France 89 (1961), 451460.Google Scholar
5. Kolettis, G., Direct sums of countable groups, Duke Math. J. 27 (1960), 111125.Google Scholar
6. Simauti, K., On abelian groups in which every neat subgroup is a pure subgroup, Comment. Math. Univ. St. Paul. 17 (1969), 105110.Google Scholar