This paper develops the energy momentum methodJor studying
stability and bifurcation of Lagrangian and Hamiltonian systems with symmetry. The method was specifically designed to deal with the stability of rotating structures. The relation with the energy-Casimir method is given and the energy-momentum method is shown to be more general. Stability of rigid body motion is given 10 illustrate the method. Some discussion of its applicability to general rotating systems and block diagonalization is also given
