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arXiv · 1511.05702

Algebras of singular integral operators with kernels controlled by multiple norms

Alexander Nagel·Fulvio Ricci·Elias M. Stein·Stephen Wainger
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Abstract

The purpose of this paper is to study algebras of singular integral operators on $\mathbb{R}^{n}$ and nilpotent Lie groups that arise when one considers the composition of Calderón-Zygmund operators with different homogeneities, such as operators that occur in sub-elliptic problems and those arising in elliptic problems. For example, one would like to describe the algebras containing the operators related to the Kohn-Laplacian for appropriate domains, or those related to inverses of Hörmander sub-Laplacians, when these are composed with the more standard class of pseudo-differential operators. The algebras we study can be characterized in a number of different but equivalent ways, and consist of operators that are pseudo-local and bounded on $L^{p}$ for $1<p<\infty$. While the usual class of Calderón-Zygmund operators is invariant under a one-parameter family of dilations, the operators we study fall outside this class, and reflect a multi-parameter structure.

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Alexander Nagel, Fulvio Ricci, Elias M. Stein, Stephen Wainger. 2015-11-18. Algebras of singular integral operators with kernels controlled by multiple norms. https://arxiv.org/abs/1511.05702

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