  We show that the exact master equation incorporating initial correlations for
open quantum systems, within the Nakajima-Zwanzig operator-projection method,
is a homegenous master equation for the reduced density matrix. We also derive
explicitly the exact master equation for a large class of bosonic and fermionic
open quantum systems incorporating initial correlations, the resulting master
equation is homogenous. We find that the effects of the initial correlations
can be fully embedded into the fluctuation dynamics through the exact
homogenous master equation. Also a generalized nonequilibrium
fluctuation-dissipation theorem incorporating the initial correlations is
obtained.
