Dynamics of the collision of two nearly equal solitary waves for the Zakharov-Kuznetsov equation

Abstract

We study the dynamics of the collision of two solitary waves for the Zakharov-Kuznetsov equation in dimension $2$ and $3$. We describe the evolution of the solution behaving as a sum of $2$-solitary waves of nearly equal speeds at time $t=-\infty$ up to time $t=+\infty$. We show that this solution behaves as the sum of two modulated solitary waves and an error term which is small in $H^1$ for all time $t\in \mathbb{R}$. Finally, we also prove the stability of this solution for large times around the collision. The proofs are a non-trivial extension of the ones of Martel and Merle for the quartic generalized Korteweg-de Vries equation to higher dimensions. First, despite the non-explicit nature of the solitary wave, we construct an approximate solution in an intrinsic way by canceling the error to the equation only in the natural directions of scaling and translation. Then, to control the difference between a solution and the approximate solution, we use a modified energy functional and a refined modulation estimate in the transverse variable. Moreover, we rely on the hamiltonian structure of the ODE governing the distance between the waves, which cannot be approximated by explicit solutions, to close the bootstrap estimates on the parameters. We hope that the techniques introduced here are robust and will prove useful in studying the collision phenomena for other focusing non-linear dispersive equations with non-explicit solitary waves.

72 pages, 4 figures

References in corpus (5)

• Numerical study of Zakharov-Kuznetsov equations in two dimensions
• Subcritical well-posedness results for the Zakharov-Kuznetsov equation in dimension three and higher
• Asymptotic stability of a finite sum of solitary waves for the Zakharov-Kuznetsov equation
• Numerical study of soliton stability, resolution and interactions in the 3D Zakharov-Kuznetsov equation
• Dynamics of two interacting kinks for the ${\varphi }^6$ model

Cited by in corpus (1)

• Asymptotic stability of a finite sum of solitary waves for the Zakharov-Kuznetsov equation