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arXiv · 2210.16164

Phase space localizing operators

Marco Fraccaroli·Olli Saari·Christoph Thiele
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Abstract

We construct phase space localizing operators in all dimensions. These are frequency localized variants of the conditional expectation operator related to a dyadic stopping time. Our construction is an improvement over the so-called phase plane projections of Muscalu, Tao and the third author in one dimension. The motivation for such operators comes from time-frequency analysis. They are used in particular to prove uniform estimates for multilinear modulation invariant operators.

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Marco Fraccaroli, Olli Saari, Christoph Thiele. 2022-10-28. Phase space localizing operators. https://arxiv.org/abs/2210.16164

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