Once we know that spacetime is foamy, then how can we make use of this fact?

Once we know how spacetime works, then does it theoretically become possible to manipulate it to our advantage? Could we find a way to bypass the Lightspeed barrier?

In naval warfare, first the Soviets and later the Americans found a way to increase the speed of torpedoes underwater, by developing the concept of Supercavitation. The idea behind supercavitation is that you shift the liquid water medium around your torpedo into vapor phase, so that your torpedo is now mostly surrounded by steam. And of course a torpedo moving through steam encounters much less resistance than if it was moving through water. This enables a supercavitating torpedo to travel much faster than it would otherwise have been able to.

If there is indeed an aether in the form of Quantum Foam, then would it be possible to develop a method of Supercavitation, to enable a spaceship to travel Faster-than-C? If we use the analogy of foam as a 2-phase medium, then we would see Quantum Foam has having 2 phases -- one being the presence of particle-antiparticle pairs, and the other being the absence of particle-antiparticle pairs. Again, under normal conditions our spacetime has both phases intermixed, which we then experience as the jittering quantum fluctuations responsible for Heisenberg's Uncertainty and DeBroglie Wavelength.

Analogous to surrounding the torpedo with water vapour, we would want our spaceship to be surrounded by an absence of particle-antiparticle pairs. This would require suppressing their spontaneous formation. Currently the only way we know to suppress these quantum fluctuations is by using a QED confinement cavity. So we have to use solid matter in order to block the fluctuations -- essentially, we're exploiting the Pauli Exclusion.

But that's no good for space travel purposes. After all, we can't generate a super-long QED confinement tube that spans the distance between earth and some star, even if we could magically transform our bodies into a stream of tiny particles to beam down those tubes for Faster-than-C purposes.

What other method could we think of? How about quantum interference at the sub-Planck scale? If we could produce a pattern of fluctuations that exactly mirrored the fluctuations appearing immediately ahead of us in space, then could we not cancel them out? But gee, quantum fluctuations are very random and superfast. We would have to be able to mirror those fluctuations identically in an equal and opposite way, which we don't know how to do.

Okay, what about trying to speed up or shorten the time/length of the quantum fluctuations, to diminish their effect? Would there be some ultra-high frequency radiation (wavelength < PlanckLength) that we could use to energize spacetime at the sub-Planck level, and affect the virtual particles?

Hmm, that sounds interesting. Is there any known barrier law or theoretical limit as to how high a radiation frequency we can achieve? What is the highest frequency achieved so far? Is there any reason why we couldn't eventually generate radiation at a frequency that corresponds to sub-Planck wavelength? How long will it take for us to get there?