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arXiv · 2009.02323

Uniform pointwise estimates for ultraspherical polynomials

Valentina Casarino·Paolo Ciatti·Alessio Martini
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Abstract

We prove pointwise bounds for two-parameter families of Jacobi polynomials. Our bounds imply estimates for a class of functions arising from the spectral analysis of distinguished Laplacians and sub-Laplacians on the unit sphere in arbitrary dimension, and are instrumental in the proof of sharp multiplier theorems for those operators.

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Valentina Casarino, Paolo Ciatti, Alessio Martini. 2020-09-04. Uniform pointwise estimates for ultraspherical polynomials. https://doi.org/10.5802/crmath.255

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