Faster than light travel may not be possible in actual fact (maybe...)

  • Thread starter Thread starter mrk
  • Start date Start date

mrk

mrk

mrk

Man of Honour
Joined
18 Oct 2002
Posts
103,821
Location
South Coast
http://www.technologyreview.com/blog/arxiv/23292/

Bad news I'm afraid -- it looks as if faster-than-light travel isn't possible after all. That's the conclusion of a new study into how warp drives would behave when quantum mechanics is taken into account. "Warp drives would become rapidly unstable once superluminal speeds are reached," say Stefano Finazzi at the International School for Advanced Studies in Trieste, Italy, and a couple of friends.

Warp drives have been the focus of science fiction writers for decades. But scientists kept them at arms length until 1994 when the idea was put on a firm (ish) theoretical footing by the Mexican physicist, Michael Alcubierre. His thinking is that while relativity prevents faster-than-light travel relative to the fabric of space time, it places no restriction on the speed at which regions of spacetime may move relative to each other.

Alcubierre imagined a small volume of flat spacetime in which a spacecraft might sit, surrounded by a highly distorted bubble of spacetime which shrinks in the direction of travel, bringing your destination nearer, and stretches behind you. He showed that this shrinking and stretching could enable the bubble--and the spaceship it contained--to move at superluminal speeds.

The conclusion is the result of classical thinking using the ideas of general relativity but physicists have long wondered what would happen if you threw quantum mechanics into the mix? Now Finazzi and pals have worked it. For a start, they say that the inside of the bubble would be filled with Hawking radiation, making life rather uncomfortable for any spacecraft within it.

They have also studied a property of a quantum field called the renormalised stress-energy tensor which should be well-behaved under normal circumstances. But in the front wall of Alcubierre's bubble travelling at superluminal speeds, the renormalised stress-energy tensor grows exponentially.

That strongly implies that such a bubble would be unstable. So it looks increasingly likely that, after a brief few years of excitement, Alcubierre's warp drive is impossible.
Click to expand...

Oh well, maybe someone will invent a FTL drive stabiliser :p
 
I thought that special relativity (time dilation, and mass gain etc.) threw any idea of warp drives out of the window years ago?
 
Yes it is news, science news, don't you see it? or was it too fast...

Also isn't wormhole travel on the same level as with the spacecraft in a spacetime bubble? since a wormhole is stretching vast areas of space and spacetime so the quantum effects would be the same on any physical craft travelling through it?

Hmm..
 
Last edited:
graphicid97grey.jpg


?
 
mrk said:
Yes it is news, science news, don't you see it? or was it too fast...
Click to expand...

I was pretty sure the scientific community had established years ago that it is impossible to travel faster than the speed of light. Even tachyons are only hypothetical.
 
Never done it myself, but my grandfather once told me a hilarious story about a hair-raising taxi ride in Rome! :D
 
You must log in or register to reply here.
Back
Top Bottom