  Why does {\bf F} equal m{\bf a} in Newton's equation of motion? How does a
gravitational field produce a force? Why are inertial mass and gravitational
mass the same? It appears that all three of these seemingly axiomatic
foundational questions have an answer involving an identical physical process:
interaction between the electromagnetic quantum vacuum and the fundamental
charged particles (quarks and electrons) constituting matter. All three of
these effects and equalities can be traced back to the appearance of a specific
asymmetry in the otherwise uniform and isotropic electromagnetic quantum
vacuum. This asymmetry gives rise to a non-zero Poynting vector from the
perspective of an accelerating object. We call the resulting energy-momentum
flux the {\it Rindler flux}. The key insight is that the asymmetry in an
accelerating reference frame in flat spacetime is identical to that in a
stationary reference frame (one that is not falling) in curved spacetime.
Therefore the same Rindler flux that creates inertial reaction forces also
creates weight. All of this is consistent with the conceptualizaton and
formalism of general relativity. What this view adds to physics is insight into
a specific physical process creating identical inertial and gravitational
forces from which springs the weak principle of equivalence. What this view
hints at in terms of advanced propulsion technology is the possibility that by
locally modifying either the electromagnetic quantum vacuum and/or its
interaction with matter, inertial and gravitational forces could be modified.
