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arXiv · 0805.4310

Integrable peakon equations with cubic nonlinearity

Andrew N. W. Hone·Jing Ping Wang
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Abstract

We present a new integrable partial differential equation found by Vladimir Novikov. Like the Camassa-Holm and Degasperis-Procesi equations, this new equation admits peaked soliton (peakon) solutions, but it has nonlinear terms that are cubic, rather than quadratic. We give a matrix Lax pair for V. Novikov's equation, and show how it is related by a reciprocal transformation to a negative flow in the Sawada-Kotera hierarchy. Infinitely many conserved quantities are found, as well as a bi-Hamiltonian structure. The latter is used to obtain the Hamiltonian form of the finite-dimensional system for the interaction of $N$ peakons, and the two-body dynamics (N=2) is explicitly integrated. Finally, all of this is compared with some analogous results for another cubic peakon equation derived by Zhijun Qiao.

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Andrew N. W. Hone, Jing Ping Wang. 2008-05-28. Integrable peakon equations with cubic nonlinearity. https://arxiv.org/abs/0805.4310

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