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CONVOLUTION OPERATORS AND HOMOMORPHISMS OF LOCALLY COMPACT GROUPS

Part of: Abstract harmonic analysis Special classes of linear operators

Published online by Cambridge University Press:  01 June 2008

CÉDRIC DELMONICO
CÉDRIC DELMONICO*
Affiliation:
EPFL SB IACS, Station 8, CH-1015 LAUSANNE, Switzerland (email: cedric.delmonico@a3.epfl.ch)
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Abstract

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Let , let G and H be locally compact groups and let ω be a continuous homomorphism of G into H. We prove, if G is amenable, the existence of a linear contraction of the Banach algebra CVp(G) of the p-convolution operators on G into CVp(H) which extends the usual definition of the image of a bounded measure by ω. We also discuss the uniqueness of this linear contraction onto important subalgebras of CVp(G). Even if G and H are abelian, we obtain new results. Let Gd denote the group G provided with a discrete topology. As a corollary, we obtain, for every discrete measure, , for Gd amenable. For arbitrary G, we also obtain . These inequalities were already known for p=2 . The proofs presented in this paper avoid the use of the Hilbertian techniques which are not applicable to . Finally, for Gd amenable, we construct a natural map of CVp (G) into CVp (Gd) .

Keywords

convolution operatorspseudomeasuresp-multiplierstransform theoremHerz algebra

MSC classification

Secondary: 43A22: Homomorphisms and multipliers of function spaces on groups, semigroups, etc. 43A25: Fourier and Fourier-Stieltjes transforms on locally compact and other abelian groups 43A45: Spectral synthesis on groups, semigroups, etc. 47B38: Operators on function spaces (general)
Type
Research Article
Information
Journal of the Australian Mathematical Society , Volume 84 , Issue 3 , June 2008 , pp. 329 - 344
Copyright
Copyright © 2008 Australian Mathematical Society

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