Comparision of quantum field perturbation theory on the light-front with the one in Lorentz coordinates

A relation between perturbation theory in light-front coordinates and the Lorentz-covariant perturbation theory is investigated. A method to find the difference between separate terms of the corresponding series without their explicit evaluation is proposed. By using this method the procedure of constructing additional counterterms to canonical Hamiltonian which compensate this difference at any finite order is worked out. For the Yukawa model the light-front Hamiltonian including all such counterterms is obtained in a closed form. Possible application of this approach to gauge theories is discussed.