Singular integral operators with kernels associated to negative powers of real-analytic functions

TL;DR

This paper studies a class of singular integral operators with kernels related to negative powers of real-analytic functions, establishing L^p boundedness under certain conditions, including non-integrable kernels and generalizations.

Contribution

It introduces new L^p boundedness results for singular integrals with kernels tied to real-analytic functions, extending classical Riesz transform and multiparameter integral theories.

Findings

Proved L^p boundedness for kernels with negative powers of real-analytic functions.

Extended results to nontranslation-invariant and Radon transform versions.

Included cases where kernels are not integrable, broadening applicability.

Abstract

Given a real-analytic function b(x) defined on a neighborhood of the origin with b(0) = 0, we consider local convolutions with kernels which are bounded by |b(x)|^(-a), where a > 0 is the smallest number for which |b(x)|^(-a) is not integrable on any neighborhood of the origin. Under appropriate first derivative bounds and a cancellation condition, we prove L^p boundedness theorems for such operators including when the kernel is not integrable. We primarily (but not exclusively) consider the p = 2 situation. The operators considered generalize both local versions of Riesz transforms and some local multiparameter singular integrals. Generalizations of our results to nontranslation-invariant versions as well as singular Radon transform versions are also proven.