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Three Loop Free Energy Using Screened Perturbation Theory

Jens O. Andersen
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Abstract

The conventional weak-coupling expansion for the pressure of a hot plasma shows no sign of convergence unless the the coupling constant $g$ is tiny. In this talk, I discuss screened perturbation theory (SPT) which is a reorganization of the perturbative expansion by adding and subtracting a local mass term in the Lagrangian. We consider several different mass prescriptions, and compute the pressure to three-loop order. The SPT-improved approximations appear to converge for rather large values of the coupling constant.

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Jens O. Andersen. 2000-08-03. Three Loop Free Energy Using Screened Perturbation Theory. https://doi.org/10.1142/9789812799913_0013

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