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PT-Symmetric Extension of the Korteweg-de Vries Equation

Carl M. Bender·Dorje C. Brody·Junhua Chen·Elisabetta Furlan
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Abstract

The Korteweg-de Vries equation u_t+uu_x+u_{xxx}=0 is PT symmetric (invariant under space-time reflection). Therefore, it can be generalized and extended into the complex domain in such a way as to preserve the PT symmetry. The result is the family of complex nonlinear wave equations u_t-iu(i u_x)^epsilon+u_{xxx}=0, where epsilon is real. The features of these equations are discussed. Special attention is given to the epsilon=3 equation, for which conservation laws are derived and solitary waves are investigated.

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Carl M. Bender, Dorje C. Brody, Junhua Chen, Elisabetta Furlan. 2006-10-02. PT-Symmetric Extension of the Korteweg-de Vries Equation. https://doi.org/10.1088/1751-8113/40/5/f02

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