RELATIVISTIC (3-DIMENSIONAL NONTOPOLOGICAL SOLITONS UNDER PERTURBATIONS(1))

We study the response of a Q-ball soliton (with an unbroken global Abe lian internal symmetry) under an arbitrary perturbation (not necessari ly Lagrangian). A method based on dynamical symmetry groups and singul ar perturbation theory is presented and the dynamics of the collective coordinates that characterize the soliton derived. The method present ed here can also be applied to study interacting Q balls perturbed, to pological solitons, nontopological solitons with an additional broken discrete symmetry, and nontopological solitons with a non-Abelian inte rnal symmetry group such as, for example, the Q lumps of the nonlinear a model with SU(2)xSU(2) global symmetry.