2025/09/24 by Hupkes, Hermen Jan, McGinnis, Joshua A., Westdorp, Rik W. S. +1
#37H10 #37K40 #37K60 #Dynamical Systems (math.DS) #FOS: Mathematics
paper · doi:10.48550/arxiv.2509.20165
We study the propagation of solitary waves in a Fermi-Pasta-Ulam-Tsingou (FPUT) lattice with small random heterogeneity in the linear spring force. Perturbed by the random environment, solitary waves lose energy through a radiative tail, resulting in gradual amplitude attenuation. As long as the wave remains coherent, we track its position and amplitude via a modulation approach. An expansion of the resulting modulation equations provides explicit predictions for the slow average amplitude decay, which we verify through numerical simulations.