Theoretical and Mathematical Physics

, Volume 137, Issue 1, pp 1448–1458 | Cite as

The Influence of Modulational Instability on Energy Exchange in Coupled Sine-Gordon Equations

  • S. D. Griffiths
  • R. H. J. Grimshaw
  • K. R. Khusnutdinova


We consider a two-component system of coupled sine-Gordon equations, particular solutions of which represent a continuum generalization of periodic energy exchange in a system of coupled pendulums. Weakly nonlinear solutions describing periodic energy exchange between waves traveling in the two components are governed, depending on the length scale of the amplitude variation, either by two nonlocally coupled nonlinear Schrödinger equations, with different transport terms due to the group velocity, or by a model that is nondispersive to the leading order. Using both asymptotic analysis and numerical simulations, we show that the effects of dispersion significantly influence the structure of these solutions, causing modulational instability and the formation of localized structures but preserving the pattern of energy exchange between the components.

coupled sine-Gordon equations amplitude equations linear waves nonlinear waves energy exchange in two-component systems modulational instability 


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Copyright information

© Plenum Publishing Corporation 2003

Authors and Affiliations

  • S. D. Griffiths
    • 1
  • R. H. J. Grimshaw
    • 1
  • K. R. Khusnutdinova
    • 1
    • 2
  1. 1.Department of Mathematical SciencesLoughborough UniversityLoughboroughUK
  2. 2.Ufa Branch, RASInstitute of MechanicsUfaRussia

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