Can the Warp Drive Go Faster Than Light?

sshai45
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Hi.

I'm curious about this: The supposed "warp drive" by Miguel Alcubierre is supposed to go faster than light. But, isn't it a warp in spacetime? Doesn't that make it like a gravity wave? But gravity waves can only go the speed of light, right? So how can the warp drive go faster?
 
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A gravity wave is a propagating change in a gravitational field, thus constrained to travel at c, away from the source system - a pair of orbitting pulsars, for example. A warp-bubble would be a moving source of space-time distortion - thus able to travel faster than light because there's no general relativistic requirement that a 'piece' of space-time travels slower than light. Whether the physics of the real world allows it to happen is a rather more difficult question to answer.
 
The Alcubierre warp drive (if it could be built) would get you there more quickly than light because it is changing the properties of space such that the warp drive ship is traveling a much shorter distance.

But in the local, warped space - it is going slower than the speed of light.

So if you would like to go to Betelgeuse and back over the coming weekend - you just have to design and build a workable warp drive.

See http://www.nasa.gov/centers/glenn/technology/warp/warpstat_prt.htm
 
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