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arXiv · 2306.00592

Phase space analysis of spectral multipliers for the twisted Laplacian

S. Ivan Trapasso
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Abstract

We prove boundedness results on modulation and Wiener amalgam spaces for some families of spectral multipliers for the twisted Laplacian. We exploit the metaplectic equivalence relating the twisted Laplacian with a partial harmonic oscillator, leading to a general transference principle for the corresponding spectral multipliers. Our analysis encompasses powers of the twisted Laplacian and oscillating multipliers, with applications to the corresponding Schr\"odinger and wave flows. On the other hand, elaborating on the twisted convolution structure of the eigenprojections and its connection with the Weyl product of symbols, we obtain a complete picture of the boundedness of the heat flow for the twisted Laplacian. Results of the same kind are established for fractional heat flows via subordination.

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S. Ivan Trapasso. 2023-06-01. Phase space analysis of spectral multipliers for the twisted Laplacian. https://arxiv.org/abs/2306.00592

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