The thermal β-function in Yang-Mills theory

Previous calculations of the thermal β function in a hot Yang-Mills gas at the one-loop level have exposed problems with the gauge dependence and with the sign, which is opposite to what one would expect for asymptotic freedom. It is shown that inclusion of higher-loop effects through a static Braaten-Pisarski resummation is necessary to consistently obtain the leading term, but alters the results only quantitatively. The sign, in particular, remains the same. It is also explored, by a crude parametrization, the effects a (non-perturbative) magnetic mass may have on these results. (author). 30 refs., 2 figs