Gribov horizon under the (lattice) microscope
  The infinite color-Coulomb energy of color-charged states is related to enhanced density of near-zero modes of the Faddeev-Popov operator in Coulomb gauge. We confirm the enhancement in numerical simulations and show that it is tied to the presence of percolating center vortex configurations. 
Jeff Greensite, Stefan Olejnik, Daniel Zwanziger