Abstract :
We first consider the origin of colour deconfinement, comparing in particular spontaneous symmetry breaking and percolation. Next we specify the onset of deconfinement in nuclear collisions through parton percolation, and with parameters determined at SPS energy, we give quantitative predictions for charmonium suppression at RHIC. Finally we show that the parton cascade model leads to similar predictions, starting from a microscopic description of the space-time evolution of the collision.
