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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

1. Bourbaki, N., Eléments de mathématique. I:Les structures fondamentales de l'analyse. Fasc. VIII. Livre III : Topologie générale. Chapitre 9: Utilisation des nombres réels en topologie générale, 2e éd., Actualités Sci. Indust., No. 1045 (Hermann, Paris, 1958).Google Scholar
2. Day, M. M., Normed linear spaces (Springer, Berlin, 1958).Google Scholar
3. Glicksberg, I., Uniform boundedness for groups, Can. J. Math. 14 (1962), 269276.Google Scholar
4. Grothendieck, A., Critères de compacité dans les espaces fonctionelles généraux, Amer. J. Math. 74 (1952), 168186.Google Scholar