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arXiv · 2109.00451

Constructive approximation on graded meshes for the integral fractional Laplacian

Juan Pablo Borthagaray·Ricardo H. Nochetto
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Abstract

We consider the homogeneous Dirichlet problem for the integral fractional Laplacian $(-\Delta)^s$. We prove optimal Sobolev regularity estimates in Lipschitz domains provided the solution is $C^s$ up to the boundary. We present the construction of graded bisection meshes by a greedy algorithm and derive quasi-optimal convergence rates for approximations to the solution of such a problem by continuous piecewise linear functions. The nonlinear Sobolev scale dictates the relation between regularity and approximability.

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Juan Pablo Borthagaray, Ricardo H. Nochetto. 2021-09-01. Constructive approximation on graded meshes for the integral fractional Laplacian. https://arxiv.org/abs/2109.00451

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