A discrete variational identity on semi-direct sums of Lie algebras
arXiv:0711.1147 · doi:10.1088/1751-8113/40/50/010
Abstract
The discrete variational identity under general bilinear forms on semi-direct sums of Lie algebras is established. The constant involved in the variational identity is determined through the corresponding solution to the stationary discrete zero curvature equation. An application of the resulting variational identity to a class of semi-direct sums of Lie algebras in the Volterra lattice case furnishes Hamiltonian structures for the associated integrable couplings of the Volterra lattice hierarchy.
18 pages