Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-15T23:22:08.611Z Has data issue: false hasContentIssue false

CONTINUITY OF MEASURABLE HOMOMORPHISMS

Published online by Cambridge University Press:  01 August 2008

JANUSZ BRZDȨK*
Affiliation:
Department of Mathematics, Pedagogical University, Podchorążych 2, 30-084 Kraków, Poland (email: [email protected])
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.

We give some general results concerning continuity of measurable homomorphisms of topological groups. As a consequence we show that a Christensen measurable homomorphism of a Polish abelian group into a locally compact topological group is continuous. We also obtain similar results for the universally measurable homomorphisms and the homomorphisms that have the Baire property.

Type
Research Article
Copyright
Copyright © 2008 Australian Mathematical Society

References

[1]Beck, A., Corson, H. H. and Simon, A. B., ‘The interior points of the product of two sets of a locally compact group’, Proc. Amer. Math. Soc. 9 (1958), 648652.Google Scholar
[2]Brzdȩk, J., ‘On the Cauchy difference on normed spaces’, Abh. Math. Sem. Univ. Hamburg 66 (1996), 143150.CrossRefGoogle Scholar
[3]Brzdȩk, J., ‘On almost additive functions’, Bull. Austral. Math. Soc. 54 (1996), 281290.Google Scholar
[4]Christensen, J. P. R., ‘Borel structures in groups and semigroups’, Math. Scand. 28 (1971), 124128.CrossRefGoogle Scholar
[5]Christensen, J. P. R., ‘On sets of Haar measure zero in abelian Polish groups’, Israel J. Math. 13 (1972), 255260.CrossRefGoogle Scholar
[6]Fisher, P. and Słodkowski, Z., ‘Christensen zero sets and measurable convex functions’, Proc. Amer. Math. Soc. 79 (1980), 449453.CrossRefGoogle Scholar
[7]Kominek, Z. and Kuczma, M., ‘Theorems of Bernstein-Doetsch, Piccard and Mehdi, and semilinear topology’, Arch. Math. (Basel) 52 (1989), 595602.CrossRefGoogle Scholar
[8]Kleppner, A., ‘Measurable homomorphisms of locally compact groups’, Proc. Amer. Math. Soc. 106 (1989), 391395.CrossRefGoogle Scholar
[9]Kleppner, A., ‘Correction to “Measurable homomorphisms of locally compact groups” 106 (1989), 391–395’, Proc. Amer. Math. Soc. 111 (1991), 1199.Google Scholar
[10]Noll, D., ‘Souslin measurable homomorphisms of topological groups’, Arch. Math. (Basel) 59 (1992), 294301.CrossRefGoogle Scholar
[11]Oxtoby, J. C., Measure and Category, Graduate Texts in Mathematics (Springer, Berlin, 1971).CrossRefGoogle Scholar
[12]Pettis, B. J., ‘On continuity and openness of homomorphisms in topological groups’, Ann. of Math. (2) 52 (1950), 293308.CrossRefGoogle Scholar
[13]Sander, W., ‘Verallgemeinerungen eines Satzes von S. Piccard’, Manuscripta Math. 16 (1975), 1125.Google Scholar
[14]Sander, W., ‘A generalization of a theorem of S. Piccard’, Proc. Amer. Math. Soc. 73 (1979), 281282.Google Scholar
[15]Sander, W., ‘Ein Beitrag zur Baire-Kategorie-Theorie’, Manuscripta Math. 34 (1981), 7183.Google Scholar
[16]Sasvári, Z., ‘On measurable local homomorphisms’, Proc. Amer. Math. Soc. 112 (1991), 603604.Google Scholar
[17]Solecki, S., ‘Amenability, free subgroups, and Haar null sets in non-locally compact groups’, Proc. London Math. Soc. (3) 93 (2006), 693722.CrossRefGoogle Scholar
[18]Stromberg, K., ‘An elementary proof of Steinhaus’s theorem’, Proc. Amer. Math. Soc. 36 (1972), 308.Google Scholar