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A noncommutative half-angle formula

Published online by Cambridge University Press:  17 April 2009

George Willis
Affiliation:
Department of Mathematics, University of Newcastle, Callaghan NSW 2308, Australia, e-mail: george@math.newcastle.edu.au
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The half-angle formulæ, familiar from trigonometry, can be used to compute the polar decomposition of the operator on l2(ℤ) of convolution by δ0 + δ1. This calculation is extended here to a non-commutative setting by computing the polar decomposition of certain convolution operators on the spaces of square integrable functions of free groups.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 2004

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