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arXiv · 1902.03161

On the size of the singular set of minimizing harmonic maps into the 2-sphere in dimension four and higher

Katarzyna Mazowiecka·Michał Miśkiewicz·Armin Schikorra
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Abstract

We extend the results of our recent preprint [arXiv: 1811.00515] into higher dimensions $n \geq 4$. For minimizing harmonic maps $u\in W^{1,2}(\Omega,\mathbb{S}^2)$ from $n$-dimensional domains into the two dimensional sphere we prove: (1) An extension of Almgren and Lieb's linear law, namely \[\mathcal{H}^{n-3}(\textrm{sing} u) \le C \int_{\partial \Omega} |\nabla_T u|^{n-1} \,d\mathcal{H}^{n-1};\] (2) An extension of Hardt and Lin's stability theorem, namely that the size of singular set is stable under small perturbations in $W^{1,n-1}$ norm of the boundary.

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Katarzyna Mazowiecka, Michał Miśkiewicz, Armin Schikorra. 2019-02-08. On the size of the singular set of minimizing harmonic maps into the 2-sphere in dimension four and higher. https://arxiv.org/abs/1902.03161

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