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arXiv · 2110.04023

Dirichlet problem for weakly harmonic maps with rough data

Gael Diebou Yomgne·Herbert Koch
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Abstract

Weakly harmonic maps from a domain $\Omega$ (the upper half-space $\Rd$ or a bounded $C^{1,\alpha}$ domain, $\alpha\in (0,1]$) into a smooth closed manifold are studied. Prescribing small Dirichlet data in either of the classes $L^{\infty}(\partial\Omega)$ or $BMO(\partial\Omega)$, we establish solvability of the resulting boundary value problems by means of a nonvariational method. As a by-product, solutions are shown to be locally smooth, $C^{\infty}_{loc}$. Moreover, we show that boundary data can be chosen large in the underlying topologies if $\Omega$ is smooth and bounded by perturbing strictly stable smooth harmonic maps.

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Gael Diebou Yomgne, Herbert Koch. 2021-10-08. Dirichlet problem for weakly harmonic maps with rough data. https://arxiv.org/abs/2110.04023

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