Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-11-19T05:17:40.589Z Has data issue: false hasContentIssue false

Rings whose additive endomorphisms are ring endomorphisms

Published online by Cambridge University Press:  17 April 2009

Manfred Dugas
Affiliation:
Baylor University, Waco TX 76798-7328, United States of America
Jutta Hausen
Affiliation:
University of Houston, Houston TX 77204-3476, United States of America
Johnny A. Johnson
Affiliation:
University of Houston, Houston TX 77204-3476, United States of America
Rights & Permissions [Opens in a new window]

Abstract

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.

A ring R is said to be an AE-ring if every endomorphism of its additive group R+ is a ring endomorphism. Clearly, the zero ring on any abelian group is an AE-ring. In a recent article, Birkenmeier and Heatherly characterised the so-called standard AE-lings, that is, the non-trivial AE-rings whose maximal 2-subgroup is a direct summand. The present article demonstrates the existence of non-standard AE-rings. Four questions posed by Birkenmeier and Heatherly are answered in the negative.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1992

References

[1]Birkenmeier, G. and Heatherly, H., ‘Rings whose additive endomorphisms are ring endomorphisms’, Bull. Austral. Math. Soc. 42 (1990), 145152.CrossRefGoogle Scholar
[2]Dugas, M., Hill, P., and Rangaswamy, K.M., ‘Butler groups of infinite rank II’, Trans. Amer. Math. Soc. 320 (1990), 643664.Google Scholar
[3]Feigelstock, S., ‘Rings whose additive endomorphisms are multiplicative’, Period. Math. Hungar. 19 (1988), 257260.CrossRefGoogle Scholar
[4]Fuchs, L., Infinite abelian groups, I (Academic Press., New York, 1970).Google Scholar
[5]Fuchs, L., Infinite abelian groups, II(Academic Press, New York, 1973).Google Scholar
[6]Jech, T., Set theory (Academic Press, New York, 1978).Google Scholar
[7]Kim, K.H. and Roush, F.W., ‘Additive endomorphisms of rings’, Period. Math. Hungar. 12 (1981), 241242.CrossRefGoogle Scholar
[8]McCoy, N.H., Rings and ideals, Carus Mathematical Monographs (The Mathematical Association of America, Fifth Impression, 1971.).Google Scholar
[9]Sullivan, R.P., ‘Research problem No. 23’, Period. Math. Hungar. 8 (1977), 313314.Google Scholar