Screened perturbation theory at four loops
نویسنده
چکیده
We study the thermodynamics of massless φ-theory using screened perturbation theory, which is a way to systematically reorganise the perturbative series. The free energy and pressure are calculated through four loops in a double expansion in powers of g and m/T , where m is a thermal mass of order gT . The result is truncated at order g. We find that the convergence properties are significantly improved compared to the weak-coupling expansion.
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ar X iv : h ep - p h / 02 10 19 5 v 1 1 3 O ct 2 00 2 1 Hard Thermal Loops and QCD
The conventional weak-coupling expansion for thermodynamic quantities in hot field theories shows poor convergence unless the coupling constant is tiny. I discuss screened perturbation theory (SPT) which is a way of reorganizing the perturbative expansion for scalar theories and hard-thermal-loop perturbation theory (HTLPT), which is its generalization to gauge theories. I present results for t...
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