Breathers and their interaction in the massless Gross-Neveu model
  The breather is a vibrating multifermion bound state of the massless Gross-Neveu model, originally found by Dashen, Hasslacher and Neveu in the large N limit. We exhibit the salient features of this state and confirm that it solves the relativistic time-dependent Hartree-Fock equations. We then solve the scattering problem of two breathers with arbitrary internal parameters and velocities, generalizing an ansatz recently developed for the baryon-baryon scattering problem in the same model. The exact analytical solution is given and illustrated with a few examples. 
Christian Fitzner, Michael Thies
hep-th hep-ph math-ph math.MP