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arXiv · 1705.00427

Symmetry-breaking in a generalized Wirtinger inequality

Marina Ghisi·Massimo Gobbino·Giulio Rovellini
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Abstract

The search of the optimal constant for a generalized Wirtinger inequality in an interval consists in minimizing the $p$-norm of the derivative among all functions whose $q$-norm is equal to~1 and whose $(r-1)$-power has zero average. Symmetry properties of minimizers have attracted great attention in mathematical literature in the last decades, leading to a precise characterization of symmetry and asymmetry regions. In this paper we provide a proof of the symmetry result without computer assisted steps, and a proof of the asymmetry result which works as well for local minimizers. As a consequence, we have now a full elementary description of symmetry and asymmetry cases, both for global and for local minima. Proofs rely on appropriate nonlinear variable changes.

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Marina Ghisi, Massimo Gobbino, Giulio Rovellini. 2017-05-01. Symmetry-breaking in a generalized Wirtinger inequality. https://arxiv.org/abs/1705.00427

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