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arXiv · 2504.09976

Nonlocal operators in divergence form and existence theory for integrable data

Abstract

We present an existence and uniqueness result for weak solutions of Dirichlet boundary value problems governed by a nonlocal operator in divergence form and in the presence of a datum which is assumed to belong only to $L^1(Ω)$ and to be suitably dominated. We also prove that the solution that we find converges, as $s\nearrow 1$, to a solution of the local counterpart problem, recovering the classical result as a limit case. This requires some nontrivial customized uniform estimates and representation formulas, given that the datum is only in $L^1(Ω)$ and therefore the usual regularity theory cannot be leveraged to our benefit in this framework. The limit process uses a nonlocal operator, obtained as an affine transformation of a homogeneous kernel, which recovers, in the limit as $s\nearrow 1$, every classical operator in divergence form.

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BibTeXRIS

David Arcoya, Serena Dipierro, Edoardo Proietti Lippi, Caterina Sportelli, Enrico Valdinoci. 2025-04-14. Nonlocal operators in divergence form and existence theory for integrable data. https://doi.org/10.1016/j.jfa.2025.111317

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