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Positivity of Dunkl's intertwining operator via the trigonometric setting

Margit Rösler·Michael Voit
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Abstract

In this note, a new proof for the positivity of Dunkl's intertwining operator in the crystallographic case is given. It is based on an asymptotic relationship between the Opdam-Cherednik kernel and the Dunkl kernel as recently observed by M. de Jeu, and on positivity results of S. Sahi for the Heckman-Opdam polynomials and their non-symmetric counterparts.

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Margit Rösler, Michael Voit. 2004-07-08. Positivity of Dunkl's intertwining operator via the trigonometric setting. https://arxiv.org/abs/math/0405368

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