Effect of strength of nonlinearity

Ensembles of FPU lattices with lattice length $N = 512$ were integrated for values of $\epsilon$ ranging from $10^{-3}$ to $10^{-1}$. Figures 4 and 5 show excellent agreement with the $\epsilon$ scaling dependences (9) and (10) predicted by the renormalized WT theory. The scaling $k_{\mathrm{knee}}\sim \epsilon^{1/2}$ had also been previously observed in [#!dls:lecfp!#].