Strong-coupling solution for a fermion-pair model

We consider a model for the condensation of fermion pairs interacting through a generalized Coulomb potential. The model gives a new outlook on chiral condensation and chiral-symmetry breaking. For strong coupling, this model exhibits a new dynamical symmetry associated with helicity conservation, allowing construction of a strong-coupling solution. The symmetry occurs for confining as well as nonconfining potentials, and is independent of the number of colors. Near the strong-coupling limit, for small fermion masses, the low-lying states are characterized by local charge neutralization and correspond to a pseudoscalar collective excitation. The number of flavors determines the symmetry group and also affects details of the approach to the strong-coupling limit.