Heaviside transform of the e ective potential in the Gross - Neveu model

Unconventional way of handling the perturbative series is presented with the help of Heaviside transformation with respect to the mass. We apply Heaviside transform to the e ective potential in the massive Gross-Neveu model and carry out perturbative approximation of the massless potential by dealing with the resulting Heaviside function. We nd that accurate values of the dynamical mass can be obtained from the Heaviside function already at nite orders where just the several of diagrams are incorporated. We prove that our approximants converges to the exact massless potential in the in nite order. Small mass expansion of the e ective potential can be also obtained in our approach.