On inverse recursion operator and tri-Hamiltonian formulation for a Kaup-Newell system of DNLS equations. (English) Zbl 0937.37047
Summary: An inverse of the recursion operator is computed and a clear presentation of a tri-Hamiltonian formulation is provided for a Kaup-Newell system of derivative nonlinear Schrödinger (DNLS) equations. Therefore all Kaup-Newell systems in the whole hierarchy of DNLS equations are tri-Hamiltonian and have an inverse hierarchy of common commuting symmetries.
MSC:
| 37K10 | Completely integrable infinite-dimensional Hamiltonian and Lagrangian systems, integration methods, integrability tests, integrable hierarchies (KdV, KP, Toda, etc.) |
| 35Q55 | NLS equations (nonlinear Schrödinger equations) |
| 37C80 | Symmetries, equivariant dynamical systems (MSC2010) |
