Heavy-quark effective theory for QCD at all chemical potentials
By means of hopping parameter and strong-coupling expansions, a dimensionally reduced effective Polyakov loop theory is obtained for heavy-quark QCD with, in principle, any number of flavours. The sign problem arising at finite real mu is not severe, leading to a calculation of the deconfinement critical line over the whole chemical potential domain. Limits of applicability of the model are also discussed.