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arXiv · 1810.05624

Integrable couplings of a generalized D-Kaup-Newell hierarchy and their Hamiltonian structures

Morgan McAnally·Wen-Xiu Ma
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Abstract

We enlarge the spectral problem of a generalized D-Kaup-Newell (D-KN) spectral problem. Solving the enlarged zero-curvature equations, we produce integrable couplings. A reduction of the spectral matrix leads to a second integrable coupling system. Next, bilinear forms that are symmetric, ad-invariant, and non-degenerate on the given non-semisimple matrix Lie algebra are computed to employ the variational identity. The variational identity is then applied to the original enlarged spectral problem of a generalized D-KN hierarchy and the reduced problem. Hamiltonian structures are presented, as well as a bi-Hamiltonian formulation of the reduced problem. Both hierarchies have infinitely many commuting symmetries and conserved densities, i.e., are Liouville integrable.

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Morgan McAnally, Wen-Xiu Ma. 2018-10-12. Integrable couplings of a generalized D-Kaup-Newell hierarchy and their Hamiltonian structures. https://arxiv.org/abs/1810.05624

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