Using the current state of each object and its linear and angular
velocity and accelerations, the resulting ballistic trajectory for
each object can be computed for this time step. Essentially we are
evolving all of the objects in the system up to the point of the next
collision. The time to collision estimate that we use for the time
step was provided by the pair at the top of the collision heap. This
heap element was removed at the beginning of the simulation loop.
Evolution of the ballistic trajectory of each object proceeds in
parallel on all processors. No communication is necessary since all
information is local to each of the processors, and speedup is linear
for this section of the parallel code.
