C. Elphick, RELATIVISTIC (3-DIMENSIONAL NONTOPOLOGICAL SOLITONS UNDER PERTURBATIONS(1)), Physical review. D. Particles and fields, 55(12), 1997, pp. 7749-7753
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.