Subgroups of the Baer–Specker group with few endomorphisms but large dual

Andreas Blass; Rüdiger Göbel

ArticleOriginal scientific text

Title

Subgroups of the Baer–Specker group with few endomorphisms but large dual

Authors ¹, ²

Affiliations

Mathematics Department, University of Michigan, Ann Arbor, Michigan 48109, U.S.A.
Fachbereich 6, Mathematik, Universität Essen, 45117 Essen, Germany

Abstract

Assuming the continuum hypothesis, we construct a pure subgroup G of the Baer-Specker group

ℤ^{ℵ_{0}}

with the following properties. Every endomorphism of G differs from a scalar multiplication by an endomorphism of finite rank. Yet G has uncountably many homomorphisms to ℤ.

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Additional information

http://matwbn.icm.edu.pl/ksiazki/fm/fm149/fm14912.pdf

Title

Subgroups of the Baer–Specker group with few endomorphisms but large dual

Affiliations

Abstract

Bibliography

Additional information