Some remarks on Lagrangian and Poisson reduction for field theories
Castrillón-López, M. and J. E. Marsden
J. Geom. and Physics 48, 52-83
Abstract:
Given a Hamiltonian system on a fiber bundle, the Poisson covariant
formulation of the Hamilton equations is described. When the fiber bundle
is a G-principal bundle and the Hamiltonian density is G-invariant,
the reduction of this formulation is studied thus obtaining the analog of
the Lie-Poisson reduction for field theories. The relation of this reduction
with the Lagrangian reduction and the Lagrangian and Poisson reduction for
electromagnetism are also analyzed.