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Students Calculate What Hyperspace Travel Would Actually Look Like
cylonlover writes "The two Star franchises (Wars and Trek) and countless science fiction movies have given generations of armchair space travelers an idea of what to expect when looking out the window of a spaceship that's traveling faster than the speed of light. But it appears these views are – if you'll excuse the pun – a bit warped. Four students from the University of Leicester have used Einstein's theory of Special Relativity to calculate what faster than light travel would actually look like to Han and Chewie at the controls of the Millennium Falcon. The fourth year physics students – Riley Connors, Katie Dexter, Joshua Argyle, and Cameron Scoular – say that the crew wouldn't see star lines (PDF) stretching out past the ship during the jump to hyperspace, but would actually see a central disc of bright light."
There are two methods of FTL being talked about here, but they are conflating the two.
Traveling via "warp" means warping space and time itself so you're moving through space at less than C, but space is shrinking in front of you and expanding behind, so the net effect is that you've moved from point A to point B in less time than it would take light travelling without warping space. (Your actual velocity may actually be zero with this method.) This is how Star Trek does it (sort of).
Traveling via "hyperspace" means punching some type of hole in space and traveling "somewhere else". Sometimes it is just a wormhole between points A and B, but it is commonly (like in Star Wars and Babylon 5) some other space within or without normal space. It's a short cut.
Nerds should know this, and yet this is the second time within a week I've seen these two ideas talked about as if they are the same thing.
(I'll leave it to someone else to explain how traveling by Guild vessel works...)
The slashdot summary is totally inaccurate. It makes it sound as though the paper calculates what would be seen by an observer going faster than c relative to the stars, but actually the paper calculates what would be seen by an observer going at v=0.9999995c.
There is also basically nothing new in this paper. The effects they describe (relativistic aberration and Doppler shifts) have been well understood for a long time. ANU has made a nice educational video showing these effects.
The question of how things would look if you could go faster than c relative to the stars is a whole different issue. Special relativity doesn't forbid relative motion faster than c, but it puts a bunch of constraints on it: (1) it can't be achieved by a continuous process of acceleration from velocities less than c; (2) if it exists, it violates causality; and (3) although special relativity is consistent with the existence of faster-than-light particles (tachyons), it is not consistent with the existence of faster-than-light observers in a universe with 3 spatial dimensions and 1 time dimension, a.k.a. 3+1 dimensions. Result #3 (no tachyonic observers in 3+1 dimensions) has been known for a long time, but it seems to keep getting rediscovered.
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You wouldn't see anything at FTL speeds as even radio waves would come on as gamma radiation. If that doesn't kill you outright you can expect your clothes to no longer fit and your tan to turn a darker shade of green whereupon you smash the controls and die anyway.
Power tends to corrupt, and absolute power corrupts absolutely.
The link is slashdotted, but if this is the story I read earlier today then they didn't do either. Instead, they figured out what it would look like at just below light speed... about 99.995% of c.
In a nutshell, it's all about the Doppler effect. Normally visible objects like stars are blueshifted into the X-ray spectrum and the only visible is the cosmic background radition, which just looks like a big blur as it's blueshifted into the visible spectrum.
...is broke. Usually when you prove a theory wrong through evidence, it gets put away in a box. Not Special Relativity, it gets bandied about as being the most wonderful thing, we'll just modify it a little to make it work...
Einstein did modify it. The resulting theory is called General Relativity. Special Relativity still works as an extremely accurate approximation in the absence of strong gravitational fields. The equations of Special Relativity are used in experimental high energy physics all the time quite successfully.
If I can be modded down for being a troll, can I be modded up for being an orc, or a balrog?
Newton's law of gravity is broken as well. The thing is that although it's inaccurate and broken, it's a really easy approximation to how gravity works that gets you results that work well enough that people still use it for most situations. SR is similar, it doesn't work in non-inertial frames but with inertial frames, it's good enough in most situations and a lot easier to use than GR.
"When you sit with a nice girl for two hours, it seems like two minutes. When you sit on a hot stove for two minutes, it