Light is scattered by zero-point oscillations of the quantified fields. Light frequency experiences a vacuum as a dispersive medium with a refractive index. In a casimir cavity, zero-point-energy between mirrors is reduced. The presence of the closely spaced mirrors break Lorentz invariance.

This is perturbative and may fail at high frequencies. The dielectric constant changes. (Magnetic susceptibility does vary with position). Casimir cavity reflective mirrors tend to become transparent at high frequencies. Also, the time it takes for electromagnetism to transverse the distance of a casimir cavity, is less than what can be predicted in the uncertainty principle of quantum mechanics. The phenomena are still possible.

The light signals become available from excited atoms. Commuters of the Maxwell Field Response functions can cease to vanish beyond the original (with mirrors absent) light cone. The quantum electrodynamics interaction between the Maxwell and Dirac fields would have to introduce delta function derivatives into the commutators on the cone.

There are zero-point photons that can collide with photons from a probe beam. Light propagation through gravitational background fields bears some resemblance to the vacuum between mirrors in a casimir cavity. This situation also lacks Lorentz invariance. There is momentum, but no energy exchanged. The mirrors absorb the recoil. The speed of light expands in a casimir cavity, making hyper-fast light speed possible.

We exploit the partial derivatives contained in the photon polarization operator to reduce gauge potentials to the field strength components themselves. Gravity and Electromagnetism use different gauge fields. There are two possible polarizations of propagation parallel to the plates in a casimir cavity. The polarization vector is parallel to the electric field.

There are many interesting implications from this research. There were many mathematical proofs given in the original articles, that I wasn't able to show in this paper. From Einstein's matter and energy equivalence principle it is very apparent that what applies to energy in exceeding light speed can also apply to matter.

If a quantum sized volume of zero-point-energy, surrounding a spacecraft was to be removed, or part of it removed, for a fraction of a second, an accelerating spacecraft would experience reduced inertia, making faster acceleration possible using the same amount of propellant energy.

If the spacecraft could exceed conventional light speed for a mere fraction of a second, it would continue to accelerate as a tachyon, and shed energy with continued acceleration. Star Travel would be possible at acceptable energies and in acceptable time periods. A similar quantum process would be required to drop below conventional light speed, and slow to approach a planet.

Of course to avoid the causality problems associated with tachyons, a means would have to be found to keep the zero-point-energy surrounding the spacecraft at a reduced level for a constant faster than conventional light speed acceleration.