The analytic structure of the QCD propagators, confinement, and deconfinement

We present the first complete calculation of the analytic structure of the zero-spatial-momentum finite-temperature Landau-gauge gluon propagator carried out at one loop by a massive deformation of QCD perturbation theory – the screened massive expansion – at temperatures ranging from $T=0$ to $T\approx 3T_c$. We find no signatures of deconfinement in the form of meaningful changes in said structure. We argue that, beyond Euclidean space, massive perturbative methods – including the Curci-Ferrari model – might be missing crucial dynamical information as a consequence of the perturbative violation of QCD’s Ward identities.