Conférence de systèmes dynamiques.
Résumé
The linear wave equation on a torus with a mass term and perturbed by a potential depending quasi-periodically on time becomes, when written in Fourier coefficients, an infinite dimensional symplectic quasi-periodic co-cycle depending on a parameter (= the mass). We shall discuss the almost reducibility of this model when potential is analytic and the quasi- periodic frequencies are supposed to satisfy certain arithmetical conditions.
