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arXiv · 2411.07712

Rate of convergence for numerical $\alpha$-dissipative solutions of the Hunter-Saxton equation

Thomas Christiansen·Katrin Grunert
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Abstract

We prove that $\alpha$-dissipative solutions to the Cauchy problem of the Hunter-Saxton equation, where $\alpha \in W^{1, \infty}(\mathbb{R}, [0, 1))$, can be computed numerically with order $\mathcal{O}(\Delta x^{{1}/{8}}+\Delta x^{{\beta}/{4}})$ in $L^{\infty}(\mathbb{R})$, provided there exist constants $C > 0$ and $\beta \in (0, 1]$ such that the initial spatial derivative $\bar{u}_{x}$ satisfies $\|\bar{u}_x(\cdot + h) - \bar{u}_x(\cdot)\|_2 \leq Ch^{\beta}$ for all $h \in (0, 2]$. The derived convergence rate is exemplified by a number of numerical experiments.

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Thomas Christiansen, Katrin Grunert. 2024-11-12. Rate of convergence for numerical $\alpha$-dissipative solutions of the Hunter-Saxton equation. https://doi.org/10.1007/s00211-025-01482-7

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