Dissipative dynamics of solitons in planar ferromagnets

Dynamics of magnetic bubbles in planar ferromagnets described by the Landau-Lifshitz equation with dissipation is analyzed. The pure O(3) sigma model has static multisoliton solutions, characterized by a number of parameters. The parameters describe a finite-dimensional manifold. A small perturbation of energy functional with respect to the sigma model forces solitons to move, Multisoliton dynamics is effectively reduced to a flow on the parameter space.