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arXiv · 2011.00313

Pseudo-differential operators with isotropic symbols, Wick and anti-Wick operators, and hypoellipticity

Abstract

We study the link between pseudo-differential operators and Wick operators via the Bargmann transform. We deduce a formula for the symbol of the Wick operator in terms of the short-time Fourier transform of the Weyl symbol. This gives characterizations of Wick symbols of pseudo-differential operators of Shubin type and of infinite order, and results on composition. We prove a series expansion of Wick operators in anti-Wick operators which leads to a sharp G{\aa}rding inequality and transition of hypoellipticity between Wick and and Shubin symbols. Finally we show continuity results for anti-Wick operators, and estimates for the Wick symbols of anti-Wick operators.

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BibTeXRIS

Nenad Teofanov, Joachim Toft, Patrik Wahlberg. 2020-10-31. Pseudo-differential operators with isotropic symbols, Wick and anti-Wick operators, and hypoellipticity. https://arxiv.org/abs/2011.00313

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