Could a warp drive work as a time machine?

[PAllen]

Was it something along the lines of what is shown starting on page 9 of the following: http://philsci-archive.pitt.edu/4908/1/GeodesicLaw.pdf ?

Similar, but it referred to Malament, and produced a more remarkable result: that that a spacelike curve can satisfy if the dominant energy condition is dropped. I'll post it if I find it again.

At some point I had seen one based on the Gralla-Wald technique, but I can't seem to find it now. However, here is one showing that using the older Geroch technique, the WEC is not enough to prevent spacelike trajectories. This paper builds on Malament's work to which you refer:

http://arxiv.org/abs/1106.2336

In effect, these types of results suggest to me that admitting generally available matter violating energy conditions is equivalent to admitting tachyonic bodies, without recourse to warp bubbles or wormholes. I personally doubt such will ever be observed.

 

[WannabeNewton]

At some point I had seen one based on the Gralla-Wald technique, but I can't seem to find it now. However, here is one showing that using the older Geroch technique, the WEC is not enough to prevent spacelike trajectories. This paper builds on Malament's work to which you refer:

http://arxiv.org/abs/1106.2336

In effect, these types of results suggest to me that admitting generally available matter violating energy conditions is equivalent to admitting tachyonic bodies, without recourse to warp bubbles or wormholes. I personally doubt such will ever be observed.

I agree, and thank you for the link! I'll read through it right after my exam tonight