[linear]

That was one of my questions. Assuming that acceleration beyond the speed of light causes you to travel back in time, won't the universe then be traveling back towards the big bang?

[RadioAstronomer]

The problem is you cannot reach the speed of light (much less surpass it). As you approach the speed of light "C" time slows down and mass increases. All of the energy in the universe could not get one single proton to obtain the speed of light. The link will provide a graph of this phenomenon:

http://www.rsgc.on.ca/math/lorenz1.html

[Salgak]

That assumes:

1. That faster-than-light (FTL) implies time travel. The equations, in one interpretation, give a result of negative time. Whatever that means. It may mean time travel, it may not. We need experimental data, and since the rules prohibit going AT the speed of light, it makes it rather difficult to go FTL. . .

2. That the galaxies themselves are moving FTL. They aren't. The underlying space-time is moving at speeds which may be FTL. The relativity equations, and the Lorentz-Fitzgerald contraction, talk about motion IN space-time, not motion OF space-time itself. . .

I know, clear as mud. . . . (g)