  In a previous work and in terms of an exact quantum-mechanical framework,
$\hbar$-independent causal and retarded expectation values of the
second-quantized electro-magnetic fields in the Coulomb gauge were derived in
the presence of a conserved classical electric current. The classical
$\hbar$-independent Maxwell's equations then naturally emerged. In the present
work, we extend these considerations to linear gravitational quantum deviations
around a flat Minkowski space-time in a Coulomb-like gauge. The emergence of
the classical causal and properly retarded linearized classical theory of
general relativity with a conserved classical energy-momentum tensor is then
outlined. The quantum-mechanical framework also provides for a simple approach
to classical quadrupole gravitational radiation of Einstein and microscopic
spontaneous graviton emission and/or absorption processes.
