Decoherence time and entropy production in high energy Heavy Ion Collisons

In high-energy hevy-ion collisons a sigifi cant amount of entropy can be produced merely by the decoherence of the individual nuclear multi-particle states. We argue that the time scales on which this happens are much shorter than 1 fm/c. Decoherence can therefore explain the very rapid onset of a behaviour which resembles that of a thermalised state of matter. The mechanisms responsible for the creation of entropy in a high energy heavy ion collision (HIC) are still purely understood. One aspect is that the decoherence of a quantum mechanical state (like the ground states of the colliding nuclei) leads to a loss of information and thus to the production of entropy according to