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arXiv · 1410.1232

Time and Band Limiting for Matrix Valued Functions, an Example

F. Alberto Grünbaum·Inés Pacharoni·Ignacio Nahuel Zurrián
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Abstract

The main purpose of this paper is to extend to a situation involving matrix valued orthogonal polynomials and spherical functions, a result that traces its origin and its importance to work of Claude Shannon in laying the mathematical foundations of information theory and to a remarkable series of papers by D. Slepian, H. Landau and H. Pollak. To our knowledge, this is the first example showing in a non-commutative setup that a bispectral property implies that the corresponding global operator of "time and band limiting" admits a commuting local operator. This is a noncommutative analog of the famous prolate spheroidal wave operator.

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F. Alberto Grünbaum, Inés Pacharoni, Ignacio Nahuel Zurrián. 2014-10-06. Time and Band Limiting for Matrix Valued Functions, an Example. https://doi.org/10.3842/sigma.2015.044

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