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arXiv · 2505.04517

A note on bilinear multipliers with convex singularities

Valentina Ciccone
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Abstract

We study bounds in the local $L^2$ range of exponents for bilinear multipliers whose symbol is the characteristic function of the epigraph of certain convex curves. We realize these bounds as a consequence of estimates that we establish, via simple arguments, for the associated exotic paraproducts. As a further application, we observe bounds beyond the local $L^2$ range for bilinear multipliers whose symbol is the characteristic function of the epigraph of convex polygonal curves associated with these paraproducts.

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Valentina Ciccone. 2025-05-07. A note on bilinear multipliers with convex singularities. https://arxiv.org/abs/2505.04517

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