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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 A Slower Speed of Light game from MIT does the same thing, just by slowing the light down to your speed rather than speeding you up to light speed. It's the same, since its all relative.
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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Big and hairy. Actually, a lot like your mom - but with better outdoor survival skills.
Is it just my observation, or are there way too many stupid people in the world?
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?
Technically, the Universe has no sides and no center.
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
That we KNOW of..... So far.
File under 'M' for 'Manic ranting'
I giving all she got captain and I don't get the lines.
After reaching ludicrous speed, everything turns to plaid.
gate and my favorite ship troopers
the universe does have a center, at the observer. most of the universe has already exceeded light speed with regards to us, we'll never see or travel to most of it.
Nothing. You would see absolutely nothing. Blackness. Empty space. Here is why:
The warp field used to push the ship would be a 100% metamaterial, which redirects all particles, including light, around the ship perfectly, and or, capturing the particles on the event shock, and preventing them from reaching you.
That's the problem with cheating by removing the ship from the causally connected universe, via a albucuierre warpdrive; being no longer causally connected means you can't see anything, because you stop interacting with the universe outside the warp field.
Ok, pedantically, you would see an insanely redshifted image of the universe you left behind, instead of empty space. But to human eyes, that heat map would appear literally black.
When you rupture the field, and spill back into being causally connected with the universe at the remote reference frame, a shitton of energy and radiation will blast out.
Piloting a ship with that kind of propulsion would require very precise calculations about the passing of local time inside the warp field, and the time frames of both site of departure, and site of destination. It would be impossible to measure spacial distance, so the unpredictable unit of variable time is all you would have to work with. Long distance navigation would be an almost absurd proposition due to this fact. This could be the fly in the ointment against this form of travel in fact.
Einstein did modify it. The resulting theory is called General Relativity.
And every time we use GPS, we're using a tool that would not work at all without general relativity.
The equations of Special Relativity are used in experimental high energy physics all the time quite successfully.
And even so, theorists were very enthusiastic about trying to modify SR accomodate the superluminal neutrino results from 2011. Unfortunately those results turned out to be due to a loose cable.
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Why is it that hyperspace looks exactly like what one sees after 8 beers?
Table-ized A.I.
What if in fact there is no way at all to exceed c? It could mean that the only way to really explore the galaxy would be with generation ships or with machines. It would be a quite depressing discovery, for it would place limits on our imagination. "Science fiction" would pass into the category of "fantasy".
The only other possibility that would work is travel that is faster-than-light from your own perspective, but not from others' - time dilation. You could make a trip to another galaxy in a single lifetime, but it would be millions of years to everyone else.
I think that some of the biggest scientific discoveries to come will not be of possibilities, but of limitations. Not what we can do in the future, but what we can't. Humankind is going to have to live with this.
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And even so, theorists were very enthusiastic about trying to modify SR accomodate the superluminal neutrino results from 2011. Unfortunately those results turned out to be due to a loose cable.
Yep, and that's a very good thing indeed. It's when science becomes dogmatic that we should worry. Taking results in contradiction with models and attempting to modify the models so that the results fit is how science works. Sometimes you can make the models work, sometimes you need entirely new models, and sometimes it's something in between.
Incorrect. Things appear to be moving at a speed that is faster than light, but they are in fact moving at a speed below that of light, and it is space itself which is at the same time expanding, causing the effective distance between those objects and us to grow at a rate which exceeds the speed of light.
They do not however travel at FTL speeds.
You wouldn't see anything at FTL speeds as even radio waves would come on as gamma radiation.
How do you know? There is no known physics which can predict what FTL travel will look like because all the known laws of physics forbid FTL. This makes as much sense as using newtonian mechanics to explain quantum tunnelling: the existence of the phenomena you are trying to explain is forbidden by the very physics you are trying to describe it with! However that is NOT what the students did - they assumed a velocity very close to the speed of light but not greater than it then threw in the word "Millenium Falcon" which clearly excited the submitter so much they didn't bother to read the article and made up what they though sounded cool.
Having now got into a thoroughly grumpy mood I'm also astounded that what used to be one question on an assignment when I was a first year physics undergrad in the UK has now somehow morphed into an undergrad journal article. These used to publish original research done by senior undergrads not act as a means to publish first year assignment solutions, especially ones which even have existing web pages providing the answer with pictures generated by a computer program that not only solves the physics but generates the actual pictures too!
GPS would work perfectly fine without relativity calculations. [...]
False and false. Relativity matters when you care about nanosecond timing.
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The paper talks about traveling at 0.9999995c, i.e. definitely relativistic speeds but not any kind of hyperspace travel.
They made some fairly straightforward blue-shift and pressure calculations. The bright spot in front of the travelers is actually the Cosmic Background Radiation, normally microwave radiation, but blue shifted towards the visible end of the spectrum. Starlight would be shifted toward X-rays in front of them and microwave behind them.
The authors don't talk about any acceleration phase, they assume the travelers simply travel at that speed and what they would see.
Essentially nothing new in this paper, but just some fun calculations.
"Han and Chewie at the controls of the Millennium Falcon [...] wouldn't see star lines stretching out past the ship during the jump to hyperspace, but would actually see a central disc of bright light."
George Lucas will need to re-edit again his movies with up-to-date CGI.
You would see light from the outside, but consider
(1) warped space bends light - this will distort it
(2) The faster you go, the more light will hit the front (including what you catch up to), less will hit the back (when your bubble of space time is moving faster than the speed of light, you'll be outrunning it), and the less time something coming in from the side will have to actually cross the threshold...
Meaning, more light in front, less from the sides/back.
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