Discretized light-cone quantization: Solution to a field theory in one space and one time dimension

In the preceding paper, the field-theoretic bound-state problem in 1+1 dimensions was mapped to the problem of diagonalizing a strictly finite-dimensional Hamiltonian matrix by quantizing at equal light-cone time. In this paper, we calculate the invariant mass spectrum for the Yukawa theory. The spectrum is shown to be independent of the momentum cutoff in the limit and more complex with increasing harmonic resolution K. The results are compared with the recent work of Brooks and Frautschi, who apply conventional space-time quantization. Because of incompatible cutoffs, we reproduce their results only qualitatively, for a rather small value of. We propose an explanation for their nonunique mass renormalization. We also discuss the straightforward application of the discretized light-cone quantization to non-Abelian field theories in 1+1 dimensions, and the generalization to 3+1 dimensions.