English

Soliton gas in integrable dispersive hydrodynamics

Pattern Formation and Solitons 2023-06-14 v3 Exactly Solvable and Integrable Systems

Abstract

We review spectral theory of soliton gases in integrable dispersive hydrodynamic systems. We first present a phenomenological approach based on the consideration of phase shifts in pairwise soliton collisions and leading to the kinetic equation for a non-equilibrium soliton gas. Then a more detailed theory is presented in which soliton gas dynamics are modelled by a thermodynamic type limit of modulated finite-gap spectral solutions of the Korteweg-de Vries and the focusing nonlinear Schr\"odinger equations. For the focusing nonlinear Schr\"odinger equation the notions of soliton condensate and breather gas are introduced that are related to the phenomena of spontaneous modulational instability and the rogue wave formation. Integrability properties of the kinetic equation for soliton gas are discussed and some physically relevant solutions are presented and compared with direct numerical simulations of dispersive hydrodynamic systems.

Keywords

Cite

@article{arxiv.2104.05812,
  title  = {Soliton gas in integrable dispersive hydrodynamics},
  author = {Gennady A. El},
  journal= {arXiv preprint arXiv:2104.05812},
  year   = {2023}
}

Comments

59 pages, 18 figures

R2 v1 2026-06-24T01:06:00.417Z