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On dissipationless shock waves in a discrete nonlinear Schrödinger equation

A. M. Kamchatnov·A. Spire·V. V. Konotop
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Abstract

It is shown that the generalized discrete nonlinear Schrödinger equation can be reduced in a small amplitude approximation to the KdV, mKdV, KdV(2) or the fifth-order KdV equations, depending on values of the parameters. In dispersionless limit these equations lead to wave breaking phenomenon for general enough initial conditions, and, after taking into account small dispersion effects, result in formation of dissipationless shock waves. The Whitham theory of modulations of nonlinear waves is used for analytical description of such waves.

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A. M. Kamchatnov, A. Spire, V. V. Konotop. 2003-06-30. On dissipationless shock waves in a discrete nonlinear Schrödinger equation. https://doi.org/10.1088/0305-4470%2F37%2F21%2F004

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