Semiclassical Skyrmion equation of motion

The Euler-Lagrange equation for the quantized Skyrmion with definite spin and isospin is derived. It turns out to be the operator equations for the conservation of the axial-vector current in the massless-pion case and the partial conservation of axial-vector current relation in the massive-pion case. Contrary to earlier claims, it admits stable rotating soliton solutions. Furthermore, it is shown that the classical equation in the Skyrme model with rigid-body quantization is a good approximation.