Restricted flows of a hierarchy of integrable discrete systems
The author considers the system consisting of \(N\) copies of the spectral problem of a constraints relating to the variational derivatives of Hamiltonian functions or eigenvalues. The systems appear to be invariant under all flows in the hierarchy and give rise naturally to discrete Euler-Lagrange equations. Integrals of motion and Lax representation for these Lagrangian systems are deduced directly from the stationary discrete zero-curvature equation for the hierarchy. It is studied how the hierarchy is related to the AKNS hierarchy in the continuous limit.
scientific article; zbMATH DE number 1328396