Periodic solutions of wave equations for asymptotically full measure sets of frequencies

2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/106066We prove existence and multiplicity of small amplitude periodic solutions of the completely resonant wave equation u_tt - u_xx + f(x,u)=0 with Dirichlet boundary conditions where f(x,u)=a_2 u^2 + a_3(x) u^3 + O(u^4) or f(x,u)= a_4 u^4 + O(u^5) for a Cantor-like set of frequencies omega of asymptotically full measure at omega=1.18 pagesAnalysis of PDEsFunctional Analysis35L05; 35B10; 37K50Periodic solutions of wave equations for asymptotically full measure sets of frequenciestext