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arXiv · hep-th/9705177

Gap equation in scalar field theory at finite temperature

Krishnendu Mukherjee
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Abstract

We investigate the two-loop gap equation for the thermal mass of hot massless $g^2ϕ^4$ theory and find that the gap equation itself has a non-zero finite imaginary part. This indicates that it is not possible to find the real thermal mass as a solution of the gap equation beyond $g^2$ order in perturbation theory. We have solved the gap equation and obtain the real and the imaginary part of the thermal mass which are correct up to $g^4$ order in perturbation theory.

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Krishnendu Mukherjee. 1998-12-24. Gap equation in scalar field theory at finite temperature. https://doi.org/10.1142/s0217732399000304

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