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The Kunze–Stein phenomenon on the isometry group of a tree

Published online by Cambridge University Press:  17 April 2009

Alessandro Veca
Affiliation:
Dipartimento di Matematica, Università di Milano, via Saldini 50, 20133 Milano, Italia e-mail: [email protected] School of Mathematics, UNSW, Sydney NSW 2052, Australia e-mail: [email protected]
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Abstract

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Let G be the group of isometries of a homogeneous tree . In the first part of this paper we decompose G in terms of certain subgroups N, ℤ, and K to obtain the related integral formula

Then, by using ideas of A. Ionescu and the formula above, we prove that and that a related maximal operator on  is bounded from L2, 1() to L2,∞(). We finally show that Lp, 1(K\G/K) is a commutative Banach algebra of convolutors for Lp(G) and give an explicit description of its Gelfand spectrum.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 2002

References

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