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Compactness in Hom(G, H)

Published online by Cambridge University Press:  20 November 2018

H. H. Corson
Affiliation:
University of Washington, Seattle, Washington
I. Glicksberg
Affiliation:
University of Washington, Seattle, Washington
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Let G be a locally compact abelian group with Bohr compactification Ga. Then [3, Theorem 1.2] any subset F of G compact in Ga is necessarily compact in G; alternatively, any closed non-compact subset F of G has its closure F in GaF; hence F \F ≠ ø. One of our aims in the present note is to give a result (Corollary 6) which asserts that F \F has no points which are Gδs, so that F\F is a perfect set. Another aim is to give an extension of a cited result of [3] in which commutativity and local compactness are essentially irrelevant, and to unify the proofs.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1970

References

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