出版社:SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要:The QCD free energy can be studied by dimensional reduction to a three-dimensional (3d) effective
theory, whereby non-perturbative lattice simulations become less demanding. To connect
to the original QCD a perturbative matching computation is required, which is conventionally
carried out in dimensional regularization. Therefore the 3d lattice results need to be converted to
this regularization scheme as well. The conversion must be carried up to 4-loop order, where the
free energy displays an infrared (IR) singularity. We therefore need a regulator which can be implemented
both on the lattice and in the continuum computation. We introduce a mass regulator
to perform Numerical Stochastic Perturbation Theory computations. Covariant gauge is fixed in
the Faddeev-Popov scheme without introducing any ghost fields.