Nonlinear self-adjointness and conservation laws of forced KdV equation

Abstract

Abstract: Using the concept of nonlinear self-adjointness and the general theorem on conservation laws that is developed by Ibragimov, nonlinear self-adjointness and conservation laws for the forced KdV equation are studied. We first discuss its self-adjointness and find that the forced KdV equation is nonlinearly self-adjoint. At the same time, formal Lagrangian for the equation is obtained. Having performed Lie symmetry analysis for the equation, we derive lots of nontrivial conservation laws for the equation according to the difference of Lie symmetries.

Key words: nonlinear equation, forced KdV equation, conservation laws, Lie symmetry, formal Lagrangian

CLC Number:

O431

References

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