If the drive were possible, then we would have all the paradoxes of traveling back in time.
The drive works by contracting the spatial metric in front of the drive, using negative energy.
What does our Minkowski & newtonian model say about the drive?
In our model, all interactions, even interactions with "negative energy", slow down time, and can also make spatial distances longer, never shorter. This is because any interaction increases the inertia of a test mass. An example is the Schwarzschild metric: time slows down and radial distances become longer.
Negative energy would create a repulsive force of "gravity". In our model, that is analogous to the repulsive force between electric charges of the same sign. If we move a test charge, then we also move some energy in the field => the inertia is larger.
We conclude that the Alcubierre drive is not possible in our model, even with hypothetical "negative energy" matter.
In the Conclusions of the previous blog post we discussed the possibility that gravitational waves in general relativity may allow faster-than-light travel. Then a kind of an Alcubierre drive could be possible in general relativity, using gravitational waves. There would be no need for negative energy matter.
We repeat our opinion that faster-than-light travel has to be forbidden in an acceptable theory of physics. We cannot allow the time travel paradoxes.
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