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A noncommutative half-angle formula

Published online by Cambridge University Press:  17 April 2009

George Willis
George Willis
Affiliation:
Department of Mathematics, University of Newcastle, Callaghan NSW 2308, Australia, e-mail: [email protected]
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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
Information
Bulletin of the Australian Mathematical Society , Volume 69 , Issue 3 , June 2004 , pp. 369 - 382
Copyright
Copyright © Australian Mathematical Society 2004

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