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arXiv · 2506.05775

On Berger's Isoperimetric Problem

Fan Kang
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Abstract

Berger's isoperimetric problem asks if the flat equilateral torus is $\lambda_1$-maximal. In 1996, Nadirashvili first gave a positive answer. In this paper, we use El Soufi-Ilias-Ros's method and Bryant's result (arXiv:1507.01485) to give a new proof.

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Fan Kang. 2025-06-06. On Berger's Isoperimetric Problem. https://arxiv.org/abs/2506.05775

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