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Quasi-periodic solutions of completely resonant forced wave equations

Massimiliano Berti·Michela Procesi
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Abstract

We prove existence of quasi-periodic solutions with two frequencies of completely resonant, periodically forced nonlinear wave equations with periodic spatial boundary conditions. We consider both the cases the forcing frequency is: (Case A) a rational number and (Case B) an irrational number.

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Massimiliano Berti, Michela Procesi. 2005-04-20. Quasi-periodic solutions of completely resonant forced wave equations. https://arxiv.org/abs/math/0504406

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