I'm given to understand that the internal symmetries of particle physics, U(1)SU(2)SU(3), does not depend on the dimensionality or curvature of the background spacetime. If the present particle symmetry is internal, than how can there be a unification of the forces that make the forces indistinguishable when the particle symmetries themselves continue to be distinctly U(1)SU(2)SU(3)? I wouldn't think that U(1)SU(2)SU(3) depends on energy since that is just motion through space which it does not depend on. Any help is appreciated. Thanks.