On products of self-small abelian groups

Authors

  • Josef DVOŘÁK Department of Algebra, Charles University in Prague Faculty of Mathematics and Physics Sokolovsk_a 83 186 75 Praha 8 Czech Republic e-mail: pepa.dvorak@post.cz https://orcid.org/0000-0002-8435-2542

Keywords:

Self-small abelian group.

Abstract

An abelian group A is called self-small if direct sums of copies of A commute with the covariant Hom(A;-) functor. The paper presents an elementary example of a non-self-small countable product of self-small abelian groups without non-zero homomorphisms between different ones. A criterion of self-smallness of a finite product of modules is given.

Mathematics Subject Classification (2010): 16D10, 16S50, 16D70.

References

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Published

2015-03-30

How to Cite

DVOŘÁK, J. (2015). On products of self-small abelian groups. Studia Universitatis Babeș-Bolyai Mathematica, 60(1), 13–17. Retrieved from https://studia.reviste.ubbcluj.ro/index.php/subbmathematica/article/view/5653

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