  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. We point out that this effect could play a
role in ultra-relativistic heavy-ion collisions.
