The infrared properties of lattice Landau gauge QCD of SU(3) are studied by measuring gluon propagator, ghost propagator, QCD running coupling and Kugo-Ojima parameter of $\beta=6.0, 16^4,24^4,32^4$ and $\beta=6.4, 32^4,48^4$ lattices. We study Gribov copy problem by parallel tempering (PT) gauge fixing of $\beta=2.2, 16^4$ SU(2) configurations. Rather unexpected features of the unique gauge(fundamental modular gauge, FMG) are observed in relation of physical values vs the optimizing function.
Categories: hep-lat