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A theorem on abstract Segal algebras over some commutative Banach algebras

Published online by Cambridge University Press:  17 April 2009

U.B. Tewari
Affiliation:
Department of Mathematics, Indian Institute of Technology, Kanpur 208016 (U.P.), India.
K. Parthasarathy
Affiliation:
Department of Mathematics, University of Calicut, Calicut, India.
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Abstract

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Let B be a commutative, semi-simple, regular, Tauberian Banach algebra with noncompact maximal ideal space Δ(B). Suppose B has the property that there is a constant C such that for every compact subset K of Δ(B) there exists a fB with = 1 on K, ‖fBC and has compact support. We prove that if A is a proper abstract Segal algebra over B then for every positive integer n there exists fB such that fnA but fn+1A. As a consequence of this result we prove that if G is a nondiscrete locally compact abelian group, μ a positive unbounded Radon measure on Γ (the dual group of G), 1 ≤ p < q < ∞ and , then .

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1982

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