Lagrangian stability of a nonlinear quasi-periodic system
The authors consider the existence of quasi-periodic solutions and the Lagrangian stability of the following quasi-periodic system \[ \frac {d^2x}{dt^2}+ G_x(x,t)= 0, \tag{1} \] where \(G(x,t)\) is quasi-periodic in \(x\) and \(t\) with basic frequencies \(\omega_1,\dots, \omega_m\) and \(\omega_{m+1},\dots, \omega_{m+n}\), respectively. The authors prove the Lagrangian stability of (1) by using KAM iterations.
scientific article; zbMATH DE number 2082142
scientific article