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arXiv · hep-th/9705133

Non-perturbative approach to the effective potential of the $λϕ^{4} theory at finite temperature

Tomohiro Inagaki·Kenzo Ogure·Joe Sato
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Abstract

We construct a non-perturbative method to investigate the phase structure of the scalar theory at finite temperature. The derivative of the effective potential with respect to the mass square is expressed in terms of the full propagator. Under a certain approximation this expression reduces to the partial differential equation for the effective potential. We numerically solve the partial differential equation and obtain the effective potential non-perturbatively. It is found that the phase transition is of the second order. The critical exponents calculated in this method are consistent with the results obtained in Landau approximation.

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Tomohiro Inagaki, Kenzo Ogure, Joe Sato. 1998-01-29. Non-perturbative approach to the effective potential of the $λϕ^{4} theory at finite temperature. https://doi.org/10.1143/ptp.99.1069

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