Long time behavior of solutions to the generalized Boussinesq equation

TL;DR

This paper analyzes the long-term behavior of solutions to the generalized Boussinesq equation, combining theoretical analysis with numerical methods to explore existence, blow-up, and solitary wave solutions.

Contribution

It provides new conditions for global existence and blow-up, proves non-existence of solitary waves for certain parameters, and employs numerical methods to explore uncharted parameter regimes.

Findings

Conditions for global solutions and blow-up in Sobolev spaces

Non-existence of solitary waves for specific parameters

Numerical generation and evolution of solitary waves

Abstract

In this paper, we study the generalized Boussinesq equation as a model for the water wave problem with surface tension. Initially, we investigate the initial value problem within Sobolev spaces, deriving conditions under which solutions are either global or experience blow-up in time. Subsequently, we extend our analysis to Bessel potential and modulation spaces, determining the asymptotic behavior of solutions. We establish the non-existence of solitary waves for certain parameters using Pohozaev-type identities. Additionally, we numerically generate solitary wave solutions of the generalized Boussinesq equation through the Petviashvili iteration method. To further examine the time evolution of solutions, we propose employing the Fourier pseudo-spectral numerical method. Our investigation extends to the gap interval, where neither global existence nor blow-up results have been theoretically established. We find that our numerical results effectively fill these gaps, supplementing the theoretical findings.