Pauli-Villars regulator as a nonperturbative ultraviolet regularization scheme in discretized light-cone quantization

We propose a solution to the problem of renormalizing light-cone Hamiltonian theories while maintaining Lorentz invariance and other symmetries. The method uses generalized Pauli-Villars regulators to render the theory finite. We discuss the method in the context of Yukawa theory at one loop and for a soluble model in $3+1$ dimensions. The model is studied nonperturbatively. Numerical results obtained with use of discretized light-cone quantization, special integration weighting factors, and the complex symmetric Lanczos diagonalization algorithm compare well with the analytic answers.