出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：In this article we report on a new proposal to treat the infrared problems of thermal QCD by
taking into account explicitly the confining influence of the Gribov horizon. In order to make
clear the possible value of such an approach, we briefly review the most important argumentswhy
a straightforward perturbative description of finite-temperature QCD is unlikely to be successful.
From the infrared problems of thermal perturbation theory one can conclude that confinement
effects and bound states probably play an important role also in the high-temperature phase.
To set the stage we recount the supposed role of the Gribov horizon for confinement, before we
turn to the application to finite-temperature theory. In the current approach it has been found that
the contributions to the free energy from the explicit inclusion of the horizon begin to set in at
order g6 – precisely where the infrared problems of thermal QCD lead to a breakdown of ordinary
perturbation theory.
From the study of observables (free energy, anomaly, bulk viscosity) we also note that for thermodynamic
observables the leading order term obtained by such an expansion in the coupling
strongly deviates from the more complete numerical solution. This can be regarded as yet another
sign for general problems of series expansions in thermal QCD
