Low energy Skyrmion-Skyrmion scattering.

We study the scattering of two Skyrmions at low energy and large separation. We use the method proposed by Manton for truncating the degrees of freedom of the system from in nite to a manageable nite number. This corresponds to identifying the manifold consisting of the union of the low energy critical points of the potential along with the gradient ow curves joining these together and by positing that the dynamics is restricted here. The kinetic energy provides an induced metric on this manifold while restricting the full potential energy to the manifold de nes a potential. The low energy dynamics is now constrained to these nite number of degrees of freedom. For large separation of the two Skyrmions the manifold is parametrised by the variables of the product ansatz. We nd the interaction between two Skyrmions coming from the induced metric, which was independently found by Schroers. We nd that the static potential is actually negligible in comparison to this interaction. Thus to lowest order, at large separation, the dynamics reduces to geodesic motion on the manifold. We consider the scattering to rst order in the interaction using the perturbative method of Lagrange and nd that the dynamics in the no spin or charge exchange sector reduces to the Kepler problem.