From deep to shallow water two-dimensional wave turbulence: Emergence of soliton gas

This article reports an investigation into the statistical properties of an ensemble of random nonlinear water waves propagating in two dimensions in a large scale wave tank (27m x30m, 35 cm deep). By varying the peak frequency of the wave spectrum, we modify the wave dispersion and observe a transition in the system's behavior. As the frequency decreases, the dynamics evolve from weak wave turbulence to a soliton gas in the shallow water regime. This transition is striking as these two theoretical frameworks are extremely different on fundamental grounds, with the former supporting an energy cascade while the latter is integrable.