We review the infrared properties of the pure Yang–Mills correlators and discuss recent
results concerning the two classes of low-momentum solutions for them reported in
literature, ie decoupling and scaling solutions. We will mainly focus on the Landau gauge
and pay special attention to the results inferred from the analysis of the Dyson–Schwinger
equations of the theory and from “quenched” lattice QCD. The results obtained from properly
interplaying both approaches are strongly emphasized.

We study the infrared behaviour of the pure Yang-Mills correlators using relations that are
well defined in the non-perturbative domain. These are the Slavnov-Taylor identity for three-
gluon vertex and the Schwinger-Dyson equation for ghost propagator in the Landau gauge.
We also use several inputs from lattice simulations. We show that lattice data are in serious
conflict with a widely spread analytical relation between the gluon and ghost infrared critical
exponents. We conjecture that this is explained by a singular behaviour of the ghost-ghost …