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arXiv · 2405.12112

Benedicks-type uncertainty principle for metaplectic time-frequency representations

Karlheinz Gröchenig·Irina Shafkulovska
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Abstract

Metaplectic Wigner distributions are joint time-frequency representations that are parametrized by a symplectic matrix and generalize the short-time Fourier transform and the Wigner distribution. We investigate the question which metaplectic Wigner distributions satisfy an uncertainty principle in the style of Benedicks and Amrein-Berthier. That is, if the metaplectic Wigner distribution is supported on a set of finite measure, must the functions then be zero? While this statement holds for the short-time Fourier transform, it is false for some other natural time-frequency representations. We provide a full characterization of the class of metaplectic Wigner distributions which exhibit an uncertainty principle of this type, both for sesquilinear and quadratic versions.

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Karlheinz Gröchenig, Irina Shafkulovska. 2024-05-20. Benedicks-type uncertainty principle for metaplectic time-frequency representations. https://arxiv.org/abs/2405.12112

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