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arXiv · 2106.09448

Minimizing under relaxed symmetry constraints: Triple and $N$-junctions

Giorgio Fusco
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Abstract

We consider a nonnegative potential $W:\mathbb{R}^2\rightarrow\mathbb{R}$ invariant under the action of the rotation group $C_N$ of the regular polygon with $N$ sides, $N\geq 3$. We assume that $W$ has $N$ nondegenerate zeros and prove the existence of a $N$-junction solution to the vector Allen-Cahn equation. The proof is variational and is based on sharp lower and upper bounds for the energy and on a new pointwise estimate for vector minimizers.

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Giorgio Fusco. 2021-06-17. Minimizing under relaxed symmetry constraints: Triple and $N$-junctions. https://arxiv.org/abs/2106.09448

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