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Improved Gaussian Approximation

Antun Balaz·Aleksandar Belic·Aleksandar Bogojevic
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Abstract

In a recently developed approximation technique for quantum field theory the standard one-loop result is used as a seed for a recursive formula that gives a sequence of improved Gaussian approximations for the generating functional. In this paper we work with the generic $ϕ^3+ϕ^4$ model in $d=0$ dimensions. We compare the first, and simplest, approximation in the above sequence with the one-loop and two-loop approximations, as well as the exact results (calculated numericaly).

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Antun Balaz, Aleksandar Belic, Aleksandar Bogojevic. 1998-10-15. Improved Gaussian Approximation. https://arxiv.org/abs/hep-th/9810122

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