Departamento de Matemática, Universidade Federal de São Carlos, Caixa Postal 676, São Carlos CEP, 13565-905 São Paulo, Brazil
Copyright © 2010 Lynnyngs Kelly Arruda. This is an open access article distributed under the
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This paper is concerned with instability of periodic travelling wave solutions of the modified Boussinesq equation. Periodic travelling wave solutions with a fixed fundamental period L will be constructed by using Jacobi's elliptic functions. It will be shown that these solutions, called dnoidal
waves, are nonlinearly unstable in the energy space for a range of their speeds of propagation and