Long-time asymptotics of 3-solitary waves for the damped nonlinear Klein-Gordon equation

We consider the damped nonlinear Klein-Gordon equation: \begin{align*} \partial_{t}^2u-Δu+2α\partial_{t}u+u-|u|^{p-1}u=0, \ & (t,x) \in \mathbb{R} \times \mathbb{R}^d, \end{align*} where $α>0$, $1\leq d\leq 5$ and energy sub-critical exponents $p>2$. In this paper, we prove that 3-solitary waves behave as if the three solitons are on a line. Furthermore, the solitary waves have alternative signs and their distances are of order $\log{t}$.

💡 Research Summary

The paper studies the long‑time dynamics of three solitary waves (3‑solitons) for the damped nonlinear Klein‑Gordon equation

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