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arXiv · 2210.17240

Infinite families of harmonic self-maps of ellipsoids in all dimensions

Volker Branding·Anna Siffert
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Abstract

We prove that for given $k\in\mathbb{N}$, $k\geq 3$, $d\in\mathbb{N}$ and each $a\in\mathbb{R}^{*}$ with \begin{align*} a^2<4d (d+k-2)(k-2)^{-2} \end{align*} the ellipsoid $E_a:=\{x\in\mathbb{R}^k\,\lvert\,a^{-2}x_1^2+x_2^2+\ldots+x_k^2=1\}$ admits infinitely many harmonic self-maps.

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Volker Branding, Anna Siffert. 2022-10-31. Infinite families of harmonic self-maps of ellipsoids in all dimensions. https://doi.org/10.1016/j.na.2025.113874

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