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arXiv · hep-th/9606155

A non-perturbative method of calculation of Green functions

V. E. Rochev
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Abstract

A new method for non-perturbative calculation of Green functions in quantum mechanics and quantum field theory is proposed. The method is based on an approximation of Schwinger-Dyson equation for the generating functional by exactly soluble equation in functional derivatives. Equations of the leading approximation and the first step are solved for $ϕ^4_d$-model. At $d=1$ (anharmonic oscillator) the ground state energy is calculated. The renormalization program is performed for the field theory at $d=2,3$. At $d=4$ the renormalization of the coupling involves a trivialization of the theory.

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V. E. Rochev. 1997-05-15. A non-perturbative method of calculation of Green functions. https://doi.org/10.1088/0305-4470%2F30%2F10%2F037

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