Schwinger Equation as Singularly Perturbed Equation

V. E. Rochev; P. A. Saponov

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arXiv · hep-th/9502142

Schwinger Equation as Singularly Perturbed Equation

V. E. Rochev·P. A. Saponov

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Abstract

A new approximation scheme for non-perturbative calculations in a quantum field theory is proposed. The scheme is based on investigation of solutions of the Schwinger equation with its singular character taken into account. As a necessary supplementary boundary condition the Green functions' connected structures correspondence principle is used. Besides the usual perturbation theory expansion which is always available as a particular solution of our scheme some non-perturbative solutions of an equation for the propagator are found in the model of a self-interacting scalar field.

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V. E. Rochev, P. A. Saponov. 1995-02-24. Schwinger Equation as Singularly Perturbed Equation. https://arxiv.org/abs/hep-th/9502142

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