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arXiv · 1910.08178

Logarithmic Bramson correction for multi-dimensional periodic Fisher-KPP equations

Beniada Shabani
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Abstract

We study the long time behavior of solutions of periodic Fisher-KPP type equations in $\mathbb{R}^n$ that arise from compactly supported initial data. We prove that propagation along a fixed direction $e\in\mathbb{S}^{n-1}$ is completely determined by an associated minimizing direction $e'$ which is unique and in a bijective correspondence with $e$. This correspondence allows us to determine the correct Bramson shift in higher dimensions and show that that the propagation along each $e$ occurs asymptotically at the speed $w_*(e)t-\frac{n/2+1}{\lambda_*(e')\,e\cdot e'}\log t+O(1)$.

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Beniada Shabani. 2019-10-17. Logarithmic Bramson correction for multi-dimensional periodic Fisher-KPP equations. https://arxiv.org/abs/1910.08178

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