Solvability of elliptic homogeneous linear equations with measure data in weighted Lebesgue spaces
Victor Biliatto, Joel Coacalle, Tiago Picon
TL;DR
This work develops a unifying framework for solving the elliptic, homogeneous, linear equation $A^{*}(D)f=\u03bcmu$ with measure data in weighted Lebesgue spaces. The authors show that solvability in $L^{p}_{w}$ for $1<p<\infty$ is characterized by finite weighted $m$-energy $\|I_m\u03bcmu\|_{L^{p}_{w}}$, and they establish a duality-based existence result when this energy is finite; for the endpoint $p=\infty$ solvability in $L^{\infty}_{1/w}$ is obtained under the operator being canceling and under testing conditions on $\u03bcmu$ and $w$, using a new weighted $L^{1}$ Stein-Weiss inequality for a special class of vector fields. A refined version for $A_1$ weights extends the earlier Moonens–Russ–Tuominen and BP results, providing two testing conditions that imply solvability. The paper also develops two-weighted inequalities, weighted $L^{1}$-type estimates for Riesz transforms, and trace/fractional inequalities, thereby unifying and extending several prior works in this area. Overall, the results offer a robust mechanism to handle measure data in weighted elliptic problems, with potential applications to PDEs with singular sources and anisotropic media.
Abstract
Let $A(D)$ be an elliptic homogeneous linear differential operator with complex constant coefficients, $ μ$ be a vector-valued Borel measure and $w$ be a positive locally integrable function on $\mathbb{R}^N$. In this work, we present sufficient conditions on $μ$ and $w$ for the existence of solutions in the weighted Lebesgue spaces $L^p_w$ for the equation $A^{*}(D)f=μ$, for $ 1\leq p<\infty $. Those conditions are related to a certain control of the Riesz potential of the measure $μ$. We also present sufficient conditions for the solvability when $p=\infty$ adding a canceling condition on the operator. Our method is based on a new weighted $L^1$ Stein-Weiss type inequality on measures for a special class of vector fields.
