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The Effective Potential for Composite Operator in the Scalar Model at Finite Temperature

G. N. J. Ananos·N. F. Svaiter
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Abstract

We discuss the $ϕ^4$ and $ϕ^6$ theory defined in a flat $D$-dimensional space-time. We assume that the system is in equilibrium with a thermal bath at temperature $β^{-1}$. To obtain non-perturbative result, the $ 1/N $ expansion is used. The method of the composite operator (CJT) for summing a large set of Feynman graphs, is developed for the finite temperature system. The ressumed effective potential and the analysis of the D=3 and D=4 cases are given.

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G. N. J. Ananos, N. F. Svaiter. 2001-02-13. The Effective Potential for Composite Operator in the Scalar Model at Finite Temperature. https://doi.org/10.1142/9789812799913_0012

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