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arXiv · 1707.05484

Sparse domination via the helicoidal method

Abstract

Using exclusively the localized estimates upon which the helicoidal method was built, we show how sparse estimates can also be obtained. This approach yields a sparse domination for multiple vector-valued extensions of operators as well. We illustrate these ideas for an $n$-linear Fourier multiplier whose symbol is singular along a $k$-dimensional subspace of $\Gamma=\lbrace \xi_1+\ldots+\xi_{n+1}=0 \rbrace$, where $k<\dfrac{n+1}{2}$, and for the variational Carleson operator.

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Cristina Benea, Camil Muscalu. 2017-07-18. Sparse domination via the helicoidal method. https://arxiv.org/abs/1707.05484

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