# Stability of Benney-Luke line solitary waves in 2D

## TL;DR

This paper proves the nonlinear stability of line solitary waves in the 2D Benney-Luke equation, extending previous linear stability results and employing methods from KP-II soliton stability analysis.

## Contribution

It establishes the nonlinear stability of line solitary waves in the 2D Benney-Luke equation, a significant advancement over prior linear stability results.

## Key findings

- Nonlinear stability of line solitary waves proven.
- Method adapted from KP-II soliton stability analysis.
- Extends understanding of water wave models.

## Abstract

The $2$D Benney-Luke equation is an isotropic model which describes long water waves of small amplitude in $3$D whereas the KP-II equation is a unidirectional model for long waves with slow variation in the transverse direction. In the case where the surface tension is weak or negligible, linearly stability of small line solitary waves of the $2$D Benney-Luke equation was proved by Mizumachi and Shimabukuro [Nonlinearity, 30 (2017), 3419--3465]. In this paper, we prove nonlinear stability of the line solitary waves by adopting the argument by Mizumachi ([Mem. Amer. Math. Soc. no. 1125], [Proc. Roy. Soc. Edinburgh Sect. A., 148 (2018), 149--198] and [arXiv:1808.00809]) which prove nonlinear stability of $1$-line solitons for the KP-II equation.