Nonperturbative Calculation of Scattering Amplitudes
  A method for the nonperturbative calculation of scattering amplitudes and cross sections is discussed in the context of light-cone quantization. The Lanczos-based recursion method of Haydock is suggested for the computation of matrix elements of the resolvent for the light-cone Hamiltonian, from which the T-matrix can be constructed. The scattering of composite particles is handled by a generalization of a formulation given by Wick. 
J.R. Hiller