ar X iv : h ep - p h / 00 08 02 7 v 1 3 A ug 2 00 0 Three Loop Free Energy Using Screened Perturbation Theory
نویسنده
چکیده
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 threeloop order. The SPT-improved approximations appear to converge for rather large values of the coupling constant.
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