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arXiv · 1404.3652

All functions are locally $s$-harmonic up to a small error

Serena Dipierro·Ovidiu Savin·Enrico Valdinoci
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Abstract

We show that we can approximate every function $f\in C^{k}(\bar{B_1})$ with a $s$-harmonic function in $B_1$ that vanishes outside a compact set. That is, $s$-harmonic functions are dense in $C^{k}_{\rm{loc}}$. This result is clearly in contrast with the rigidity of harmonic functions in the classical case and can be viewed as a purely nonlocal feature.

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Serena Dipierro, Ovidiu Savin, Enrico Valdinoci. 2015-03-16. All functions are locally $s$-harmonic up to a small error. https://arxiv.org/abs/1404.3652

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