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On continuity of derivations and epimorphisms on some vector-valued group algebras

Published online by Cambridge University Press:  17 April 2009

Ramesh V. Garimella
Affiliation:
Department of Mathematics, Tennessee Technological University, Cookeville TN 38505, United States of America, e-mail: [email protected]
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Abstract

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For a locally compact Abelian group G and a commutative Banach algebra B, let L1(G, B) be the Banach algebra of all Bochner integrable functions. We show that if G is compact and B is a nonunital Banach algebra without nontrivial zero divisors, then (i) all derivations on L1(G, B) are continuous if and only if all derivations on B are continuous, and (ii) each epimorphism from a Banach algebra X onto L1(G, B) is continuous provided every epimorphism from X onto B is continuous. If G is noncompact then every derivation on L1(G, B) and every epimorphism from a commutative Banach algebra onto L1(G, B) are continuous. Our results extend the results of Neumann and Velasco for nonunital Banach algebras.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1997

References

[1]Bade, W.G. and Curtis, P.C. Jr, J. Funct. Anal. 29 (1978), 88103.CrossRefGoogle Scholar
[2]Curtis, P.C. Jr, ‘Derivations on commutative Banach algebras’, in Proceedings, Long Beach, 1981, Lecture Notes in Math. 975 (Springer-Verlag, Berlin, Heidelberg, New York, 1983), pp. 328333.Google Scholar
[3]Cusack, J., ‘Automatic continuity and topologically simple radical Banach algebras’, J. London Math. Soc. 16 (1977), 493500.CrossRefGoogle Scholar
[4]Dales, H.G., ‘Automatic continuity: A survey’, Bull. London Math. Soc. 10 (1978), 129183.CrossRefGoogle Scholar
[5]Diestel, J. and Uhl, J.J., Vector measures, Math. Surveys 15 (Amer. Math. Soc, Providence, RI, 1977).CrossRefGoogle Scholar
[6]Garimella, R., ‘On separating ideals of commutative Banach algebras’, in Lecture Notes in Pure and Applied Mathematics 175 (Marcel Dekker, Inc., 1996), pp. 181185.Google Scholar
[7]Garimella, R., ‘On nilpotency of the separating ideal of a derivation’, Proc. Amer. Math. Soc. 117 (1993), 167174.CrossRefGoogle Scholar
[8]Johnson, G.P., ‘Space of function with values in a Banach algebra’, Trans. Amer. Math. Soc. 92 (1959), 411429.CrossRefGoogle Scholar
[9]Neumann, M.M., ‘Automatic continuity of linear operators’, in Functional analysis, surveys and recent results II 38, North-Holland Math. Studies (North-Holland, Amsterdam, Ney York, 1980), pp. 269296.CrossRefGoogle Scholar
[10]Neumann, M.M. and Velasco, M.V., ‘Continuity of epimorphisms and derivations on vector-valued group algebras’, (preprint).Google Scholar
[11]Rudin, W., Fourier analysis on groups (Interscience, New York, London, 1962).Google Scholar
[12]Sinclair, A.M., Automatic continuity of linear operators, London Math. Soc. Lecture Notes 21 (Cambridge University Press, Cambridge, 1976).CrossRefGoogle Scholar