Real time dynamics of colliding gauge fields and the “glue burst”

The Yang-Mills equations provide a classical mean field description of gauge fields. In view of developing a coherent description of the formation of the quark gluon plasma in high energetic nucleus-nucleus collisions we study pure gauge field dynamics in $3+1$ dimensions. In collisions of wave packets, numerically simulated on a SU(2) gauge lattice, we study transverse and longitudinal energy currents. For wave packets with different polarizations in color space, we observe a time-delayed fragmentation after the collision resulting in a rapid expansion into transverse directions. We call this phenomenon the “glue burst.” An analysis of the Yang-Mills equations reveals the explanation for this behavior. It is pointed out that this effect could play a role in ultrarelativistic heavy-ion collisions.