Symmetry breaking in light-front $\phi^4$ theory
  We consider the symmetric and broken phases of light-front $\phi^4$ theory in two dimensions. In both cases the mass of the lowest state is computed and its dependence on the coupling used to infer critical coupling values. The structure of the eigenstate is examined to determine whether it shows the signs of critical behavior, specifically whether the one-body sector becomes improbable relative to the higher Fock sectors. In attempts to establish this behavior, we consider both sector-independent and sector-dependent constituent masses. 
J.R. Hiller
hep-th