We solve the quantum Vlasov equation for fermions and bosons, incorporating
spontaneous pair creation in the presence of back reactions and collisions
. Pair creation is initiated by an external impulse field and the source te
rm is non-Markovian. A simultaneous solution of Maxwell's equation in the p
resence of feedback yields an internal current and electric field that exhi
bit plasma oscillations with a period tau(pl). Allowing for collisions, the
se oscillations are damped on a time scale tau(r) determined by the collisi
on frequency. Plasma oscillations cannot affect the early stages of the for
mation of a quark-gluon plasma unless tau(r)much greater than tau(pl) and t
au(pl) similar to 1/Lambda(QCD)similar to 1 fm/c. [S0556-2821(99)06123-8].