Thread:Ghelæ/@comment-1073312-20131104182752/@comment-47205-20131106172904

Roughly, the idea is: in frames where a starship's FTL jump is backwards in time, two duplicate starships appear: there are two ships going forwards in time (one that has not yet jumped and one that has finished jumping) and one ship going backwards in time in-jump, i.e. one ship pre-jump and post-jump, but three ships during the jump. However, the four-momenta of these duplicates cannot cancel out (as the four-momentum is tangent to the worldline, so such a thing would require the worldline of the ship to go directly back on itself, which isn't what happens in an FTL jump), and therefore conservation of four-momentum is violated in these frames (but only in these frames, which under the principle of relativity is a problem).

This isn't a proof (I can think of where loopoles might arise, but lack the knowledge of general relativity to tell if they do), but it's a thought.

As for Lunarai-Khan's visit to a trench battle, a resource-poor planet that was colonised with minimal technology and largely neglected by the DCP might not be able to manufacture deadlock-breaking machines, so who knows?