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arXiv · hep-lat/9506019

Variational Study of the Phase Transition at Finite T in the $λϕ^4 $-Theory

G. Palma·J. C. Rojas
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Abstract

Assuming triviality of the 4-dimensional $λϕ^4$-theory we compute the effective potential by means of a self consistent Feynman-Bogoliubov method. This potential $U_{eff}^{FB}$ depends on a UV-cutoff, which is fixed by a stability condition for the gap-equation for the plasma mass. It shows a second order phase transition at zero temperature, in agreement with a large amount of analytical and RG analysis as well as Monte Carlo numerical evidence. As the cutoff $Λ$ is removed the renormalized self coupling constant $λ_R$ goes to zero consistent with the claim of triviality. At finite temperature the phase transition becomes weakly first order.

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G. Palma, J. C. Rojas. 1995-06-12. Variational Study of the Phase Transition at Finite T in the $λϕ^4 $-Theory. https://doi.org/10.1016/0920-5632(96)00157-0

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