Speaker
Description
The breaking of center symmetry in pure Yang-Mills theories has been connected to the confinement/deconfinement transition on the lattice, but continuum results did not show the same signatures. I will discuss the longitudinal or (chromo-)electric Yang-Mills gluon propagator in the recently proposed center-symmetric Landau gauge at finite temperature. We use the Curci-Ferrari model which accounts for lattice data in the deep infrared, showing massive behaviour of the gluons. This model allows us to rely on perturbative calculations. At one-loop order in the SU(2) case, the so-obtained longitudinal gluon propagator provides a clear signature for Z2 center-symmetry breaking with a singular behavior, characteristic of a continuous phase transition. This is in sharp contrast with what is found within the standard Landau gauge. We also identify various signatures for Z3 center-symmetry breaking in the SU(3) case in the form of genuine order parameters. Our results open new ways of identifying the transition from correlation functions both within continuum approaches and on the lattice.
