Experimental evidence of hydrodynamic instantons and their unifying role in the theory of rogue waves

Giovanni Dematteis
Università degli Studi di Torino
We interpret the formation of rogue waves in a wave flume in light of tools of large deviation theory. By numerical optimization we compute the instantons of the problem, i.e. the most likely realizations leading to extreme surface elevations via the governing nonlinear Schroedinger dynamics. We show that strikingly the typical extreme events of the experiment closely follow the instanton evolution, with small fluctuations around it. This is true accross all of the explored forcing regimes, unifying and extending the existing limiting results for the linear and highly nonlinear cases.