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arXiv · 1307.2474

Finite difference method for a general fractional porous medium equation

Félix del Teso·Juan Luis Vázquez
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Abstract

We formulate a numerical method to solve the porous medium type equation with fractional diffusion \[ \frac{\partial u}{\partial t}+(-\Delta)^{\sigma/2} (u^m)=0 \] posed for $x\in \mathbb{R}^N$, $t>0$, with $m\geq 1$, $\sigma \in (0,2)$, and nonnegative initial data $u(x,0)$. We prove existence and uniqueness of the solution of the numerical method and also the convergence to the theoretical solution of the equation with an order depending on $\sigma$. We also propose a two points approximation to a $\sigma$-derivative with order $O(h^{2-\sigma})$.

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Félix del Teso, Juan Luis Vázquez. 2013-07-09. Finite difference method for a general fractional porous medium equation. https://arxiv.org/abs/1307.2474

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