Multiple periodic solutions for an asymptotically linear wave equation. (English) Zbl 0465.35007
MSC:
35B10 | Periodic solutions to PDEs |
35L05 | Wave equation |
58E05 | Abstract critical point theory (Morse theory, Lyusternik-Shnirel’man theory, etc.) in infinite-dimensional spaces |
35B05 | Oscillation, zeros of solutions, mean value theorems, etc. in context of PDEs |
35A15 | Variational methods applied to PDEs |