The isospin dependence of the spin-orbit interaction in light neutron rich
nuclei is investigated in the framework of relativistic mean field theory. The
magnitude of the spin-orbit potential is considerably reduced in drip line
nuclei, resulting in smaller energy splittings between spin-orbit partners. The
effect does not depend on the parametrization of the effective Lagrangian. The
results are compared with corresponding calculations in the non-relativistic
Skyrme model.Comment: 8 Pages, LateX, 4 P.S. Figures, submit. Phys. Lett.