Fun with baby-skyrmions

We consider the limiting case of the O(3) nonlinear sigma model where the k inetic term (equivalently the spin-stiffness term) is absent. The model obt ained has an interesting integrability. The static energy functional admits invariance under area preserving diffeomorphisms. The equations of motion can be analytically solved for many cases. Finally solutions are exhibited that correspond to closed strings for the static three-dimensional theory, defined on S-3 and R-3.