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arXiv · 2302.07553

Existence of multi-dimensional pulsating fronts for KPP equations: a new formulation approach

Liangliang Deng·Arnaud Ducrot
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Abstract

This paper is concerned with the existence of pulsating travelling fronts for a KPP reaction-diffusion equation posed in a multi-dimensional periodic medium. We provide an alternative proof of the classic existence result. Our proof relies largely on the construction of a wave profile under a moving frame, which avoids many technical difficulties in dealing with degenerate elliptic equations. Intriguingly, our analysis also yields that the profile of the front propagating along each rational direction in $\mathbb{S}^{N-1}$ is periodic in time.

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Liangliang Deng, Arnaud Ducrot. 2023-02-15. Existence of multi-dimensional pulsating fronts for KPP equations: a new formulation approach. https://arxiv.org/abs/2302.07553

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