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arXiv · hep-ph/9703414

Resummation of phi^4 free energy up to an arbitrary order

Jens Reinbach·Hermann Schulz
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Abstract

The consistency condition, which guarantees a well organized small-coupling asymptotic expansion for the thermodynamics of massless $ϕ^4$-theory, is generalized to any desired order of the perturbative treatment. Based on a strong conjecture about forbidden two-particle reducible diagrams, this condition is derived in terms of functions of four-momentum in place of the common toy mass in previous treatments. It has the form of a set of gap equations and marks the position in the space of these functions at which the free energy is extremal.

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Jens Reinbach, Hermann Schulz. 1997-07-15. Resummation of phi^4 free energy up to an arbitrary order. https://doi.org/10.1016/s0370-2693(97)00563-7

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