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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...)
traveling at the speed of light, only the view would be a smaller dot.
The Kruger Dunning explains most post on
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.
Hyperspace travel != FTL
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?
Isn't the universe expanding from the center close to the speed of light, making the opposing side of the universe an example of this?
so when you die and head towards the white light, can it be said you are dying at the speed of light?
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.
Now I can start working on my spaceship.
Hyperspace travel wouldn't look like anything special since you're fixed in space (or traveling at subluminal speeds) and doing the bulk of your travel in hyperspace. (And let's face it - that's pure fantasy.)
FTL travel wouldn't look like anything at all either since as you approach the speed of light time slows down for you. If you traveled at the speed of light you would reach your destination instantly (and you'd only be stopped by either colliding with something or being slowed by something, likely a black hole sucking you in to your doom). If you traveled faster than the speed of light you would break all of causality. Not gonna happen.
surely the whole point of hyperspace is to be a plot device where one can avoid unfortunate physical laws that would otherwise mess up a story, like momentum (these star-ships routinely crash or make sharp turns at millions of miles per hour and the crew-members just fall over gently or brace themselves against pillars), where even Heisenberg experiences no uncertainty and in particular where special relativity apparently does not apply.
Nullius in verba
...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
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
that is not true, cosmologists know that our observable universe is a small part of the whole, most of which is moving faster than light away from us (and so will never be seen). In fact, we can only ever see or travel to something on the order of 1E-23 of the whole; the rest is accelerating away from us and has already passed lightspeed relative to earth.
Well, since it would go against every established theory, observation and experiment so far, you're free to to propose your magnificient insight with the physics community. After all, your "That we know of.. so far" argument can be used to believe in anything.
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.
In that movie, you also have laser guns that shoot slower that the speed of light! It was good entretainment when was just released and I was a little kid, but that is it!
He describes this in The City and the Stars, and possibly in an earlier work.
Lets start refering to The War Against Terror by it's initials. . .
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.
http://www.youtube.com/watch?v=BwJtYmNpINI
Will I need to bring jelly babies?
This space for rent
Looks like we now know what slashdotting looks like.
http://cdn.memegenerator.net/instances/400x/33444159.jpg
If you figure time moves at 1C, since Sunlight takes 8 minutes to reach the Earth, the reflections of that are what we see on objects here... If you are traveling at 1C away from Earth, it will look like everything stopped right when you reached 1C. The light will be moving just as fast as you.
When you fly towards something, it will seem like time is going twice as fast. The normal motion, and the amount of 'light' you are going through is twice as much as normal.
But Stars and galaxies next to you or off in the distance will 'move' a little, but are still going to be way too far away.
If it's warp speed, it's a compress space thingy. Lights should be able to pass through compress space, so, theoretically, people on spaceship that travels through warp space should be able to see light from outside.
But if that spaceship travels faster than light - that is, if that's possible at all - then no outside light should be visible.
About hyperspace - since it's a puncturing a hole in the space/time thing, ... light travels _within_ the space/time constraint, so, there should be no light in the hyperspace, either.
Muchas Gracias, Señor Edward Snowden !
This calculation isn't really relative to anything, so it could quite easily be wrong. What would be far more useful is if the students showed an animation of how perception changes as you *accelerate* *into* hyperspace.
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.
"Screw Sun, cross-platform will never work. Let's move on and steal the Java language." - Visual J++ Product Manager
Everyone knows that once you pass a certain threshold it goes plaid.
The only thing necessary for evil to triumph is for it to be pitted against a slightly greater evil
Don't go into the light, Luke!
Sheesh, evil *and* a jerk. -- Jade
Red Dwarf - Future Echoes
Leela: "Is all the work done by children?" Alien: "No, not the whipping."
That we KNOW of..... So far.
It isn't possible to accelerate to the speed of light. There's nothing that says you can't "jump" to the speed of light or multiples thereof. We know of particles (photons to name just one) that do this.
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.
Fair point.... but history is overflowing with examples of people asserting "X is impossible", for various values of X, and they were ultimately proven wrong.
It's simply much more honest to say that we just don't know of any way to travel faster than light than to casually assert its impossibility as factual.
File under 'M' for 'Manic ranting'
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.
I'm just curious.
Except: If you were traveling at the speed of light, time would stop. So you wouldn't see a damned thing because the universe would end instantaneously for you. Also you'd implode into a singularity and devour all the energy in the universe to achieve light speed, but lets not let physics get in the way.
not a screen displaying a graphic representation of data gathered from sensors way broader than visible light; Windows being, you know ... a bit leaky and fragile.
You seem to regard science as some kind of dodge... or hustle.
So, how do those Heisenberg compensators work, Scotty?
Do not mock my vision of impractical footwear
Even so, if the universe is a simulation one would expect to see alert messages such as "Please wait... Loading level 2" or "Undefined pointer at 0xa0123ebf6a78ca2a@20010db8:00000000:0000ff00:00428329"
Still nobody has answered whether your headlights will work.
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my god these people are stupid, and so is just about every replier.
this is NOT what it would look like at all, the whole idea of red/blue shift is also incorrect because...
it fails to take into account perspective, the universe is a HUGE place, there's this thing called "distance"
you MAY be traveling at just under c, or at c or above c (relatively speaking) however this is NOT what happens and NOT what it looks like.
it just means you're moving faster, the distance between the stars didn't change,
ok, if you're at 0.5 above c relatively speaking, and the distance between two stars is 10 lightyears, it still takes a LOT of time to travel that distance,
your motion relative to them will just be faster, not beyond your ability to see them. augh!
if a star is 10 light years away from where you are traveling and you dont go near it, it will only move in your view a tiny bit relative to you and the other objects around you.
they've totally forgotten about RELATIVITY, all objects, not just one in reference to your ship. but everything else around you.
I bet these same morons think that FTL means time travel, guess what, it doesn't!
idiots.
And every time we use GPS, we're using a tool that would not work at all without general relativity.
GPS would work perfectly fine without relativity calculations. The speeds and distances involved with satellites are nowhere near those required to negate calculations based on basic kinetics and triangulation. And even with relativity calculations, the satellites' timers are still off enough that they are generally re-calibrated daily.
(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.
I'm curious (but can't deal with 30 pages of relativistic physics right now). Can you answer one summarizing question, please?
Is the conclusion that such observers can't exist because:
1) tachyonic particles can't interact to form an observer,
2) if they could form an observer, the space of the observer would have something other than a 3 + 1 dimensionality, or
3) Such an observer couldn't interact with non-tachyonic matter in our 3+1 spacetime in a way that would qualify as "observing"?
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
http://www.news.cornell.edu/releases/Jan98/TigerBeetle.bpf.html
I assume The Programmers could handle a try-catch.
Unity? Screw that: XFCE. Slashdot Beta? Screw that: SoylentNews. Australis? Screw that: Pale Moon. UX developers DIAF
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!
The only viable stardrive is one that alters the local gravitational constant. It takes it way down, (or up maybe) in a bubble around the ship. Although it may, this mechanism doesn't necessarily alter any wavelengths of any EM inside it. So starlight that you ran up on, would enter your local bubble as you approached, be affected by your warp drive the same as you, and strike the surface of your ship as starlight, relative to you. In your local bubble, you're not going very fast; nothing approaching c.
So, starlight is still starlight, not gamma rays or radio waves when you see it. A useful stardrive would go some hundreds of times c. Then the fun part is the fact that you're running up on light that was emitted behind you, as well as the light in your path from stars in front. Also, light traveling perpendicular to your path; you're going to run up on that too.
I gotta believe that what ends up shining through the window would be a jumbled mess.
Quite well, thank you.
GPS would work perfectly fine without relativity calculations. [...]
False and false. Relativity matters when you care about nanosecond timing.
Range Voting: preference intensity matters
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.
Even if it were possible, to be consistent with current observations of relativistic effects, it would imply the kind of mind-bending time-travel paradoxes that sci-fi writers simply never, ever want to touch. You can't have a world like Star Trek without implying deeply broken causality.
No kidding!!! What do you say at this point?
The Bloater Drive: http://en.wikipedia.org/wiki/Bloater_Drive#Bloater_Drive
I always thought that would be neat.
Don't be apathetic. Procrastinate!
"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.
Taking their investigations one step further, the students calculated that, despite being the fastest hunk of junk in the galaxy, the Millennium Falcon would also need to pack some extra energy to overcome the pressure exerted from the intense X-rays from stars that would push the ship back and cause it to slow down. The students say the pressure exerted on the ship would be comparable to that felt at the bottom of the Pacific Ocean.
Pressure? Really? Photons have no mass, how are they expected to apply a pressure on the hull?
OK, but I hope I get some understanding if someone does answer these few question to me:
How do we know whether it is the space expanding, rather than stuff actually moving faster than light? To me, the principle of relativity makes this idea basically interchangeable. Moving space == space moving around us. I understand the current theory is, that empty space tend to expand, that is it's inherent physical property. But how can you make a distinction, let's say, below the speed of light? Let's say you spot a star, or galaxy rather to get some perceivable results, calculate of its red-shift and we can come up with it's speed/velocity. How do you split this single value to space expansion and speed?
Furthermore, the same goes to warp drive. It is mentioned in many pop-sci tv program, and it is said that it doesn't violate GR, though it is mere speculation that we could actually build one. So, from the point of view of GR, warp-drive is viable concept for FTL. I would not call it misnomer, because if you light a torch and than move space around you faster than light, than you literally will end up at your destination before the light ray reaches the spot. In the case of hypothetical warp drive, sitting in the ship, you can say easily the universe speeds past you. For an external observer, you would look coasting with a normal speed, assuming that you don't go fater than c and the observer would not be able to tell that you're using an warp-drive.
It's going to be great. ET will shoot at TIE fighters with a walkie talkie while the genie from Aladdin flies around on a magic carpet. Harrison Ford will probably play a cameo both as Indianna Jones and as an octagenarian Han Solo.
I think this is the weak point of many popular explanation of SR/GR. The speed of light is presented as a speed limit but since there's a principle of relativity at work, I don't think it is particularly good way to look at it.
The speed of light looks the same for any observer in any reference frame. When going through the motions of special relativity, this comes with a number of consequential statements, such as that observers performing uniform motion in respect to each other would find that time passes for the other at different rate from their own. Or that, if an object is accelerating toward the speed of light in respect to the observer, you will see the same invested force causes less and less increase in the object's kinematic energy.
This is interpreted as a speed limit indeed, because to reach the speed of light, you would have to see infinite amount of energy dumped in to the kinetic energy of the object which leads us to a mathematical impasse, singularity. Hence anything that needs kinetic energy to move, must be accelerated by an infinite amount of force to reach this speed, or in other words, it's resistance to move grows by the increasing velocity of the object in respect to the observer. However, two observer would disagree with the amount of this energy depending on their relative speed to the observed object. Hence, it is in the infinity/speed of light where these observation would meet anyway.
The reason why people don't like to accept this because it sounds severely limiting how our species could spread in the universe. This is a partial misconception. Since the effect of time dilation, if we would accelerate just a bit under 99% of c, it would mean that time aboard would pass 7 times slower than on earth. As you approach the speed of light in respect to Earth (which has very low speed in respect to the rest of the stars and galaxies we would like to conquer compared to our ship, Leonora Christine), the twin paradox will get more and more extreme, to the point where the traveller would loose any hope to get in touch with the original Earth and human civilization that sent him away, nevertheless will see herself passing light year distances even perhaps in matter of seconds, because from his point of view the time dilation looks like that the universe in the direction of her heading goes through length contraction, thus the space to cover looks radically shortened compared to the measure made on Earth. Thus it is theoretically possible to coast the known universe in a single human lifetime without discovering completely new set of physics. Well, at least in regards to relativity, because I'm not sure if there's physical possibility to construct such a spaceship that can be accelerated with only interstellar medium and also keep the travellers alive.
That's why I feel deeply disturbed by "geeks" who are fan of Star Trek and alike. It has so many disagreements with reality that suspension of belief for a person with a simple grasp of science and physics is impossible.
Gravitation, photon torpedo, navigational problems, SR/GR, biology, culture, social relations.... everything is broken in that universe.
"The people of your world once believed the world was flat. Columbus proved it was round. They said the sound barrier could never be broken!... It was broken. They said warp-speed could not be accomplished."
Without the SSL error on it?
Very well, but they do tend to act up a bit every few years.
Here's the thing: Star Trek, when you get down to the bottom of it, is an allegory. All those details have nothing to do with what the stories are really about.
And the same thing happens in almost all fiction - fiction, by its nature, simplifies and distorts. The vast majority of romance novels have little to nothing to do with what real-world relationships are like. The vast majority of detective novels have nothing to do with what real-world detectives do. The vast majority of spy novels have nothing to do with what real-world spies do. And so, in turn, the vast majority of science fiction has nothing to do with real-world science.
Suspending disbelief is about learning to enjoy the story for what's good in it. Of course, sometimes there aren't enough good parts to justify the bad - but that's a judgment each viewer has to make on their own.
...by Carl Sagan, among others
http://www.youtube.com/watch?v=lPoGVP-wZv8
The relevant bit comes at about 1:30
"celeritius" is velocity in Latin. Scientists used to write mostly in Latin until the 1800s.
My comment wasn't because necessarily I believe that we might discover some way to exceed the speed of light in the future, it's more because I see such generalizations as being less honest with ourselves about how much we actually know about the universe. I actually *DON'T* think that there might be any way to ever go faster than the speed of light, but I certainly don't *REALLY* know that... it's a belief that comes from what I already understand to be true. But there's absolutely nothing inherent in that understanding that prevents it from actually being incomplete, or even entirely wrong.
All we can honestly and positively say with respect to our knowledge is that based on our current understanding of the universe, there is no known way to ever get something moving faster than the speed of light. Simply asserting it to be impossible without such qualifiers exaggerates our current understanding of the universe by such a degree that it cannot possibly be anything more than a hypothesis and personal belief (even if it were factually true).
File under 'M' for 'Manic ranting'
I counter with...the manual (section 1.4.2.8 PVT Calculations, p. 1-14):
When the receiver has collected pseudorange measurements, deltarange measurements, and
navigation data from four (or more) satellites, it calculates the navigation solution, PVT. Each
navigation data message contains precise orbital (ephemeris) parameters for the transmitting
satellite, enabling a receiver to calculate the position of each satellite at the time the signals were
transmitted. The ephemeris data is normally valid and can be used for precise navigation for a
period of four hours following issue of a new data set by the satellite. New ephemeris data is
transmitted by the satellites every two hours.
And until those satellites tack an extra five zeroes onto the end of their speeds, classical physics still works.
If you are going ~1/3 the speed of light a red light at a traffic intersection would appear green.
http://what-if.xkcd.com/14/
I actually went through a period of intense existential crisis the last time I read a book on relativity and reminded myself that space opera simply isn't a future our species will ever experience. It passed, though. (Reading some old Arthur C. Clarke and reminding myself of the possibilities in a slower-than-light universe perked me up.) Space opera is fantasy; provided self-consistency is maintained I can live with it.
No kidding!!! What do you say at this point?
Probably violating several sacred canons of Trekkerdom here, but: what if warp speeds are in fact achieved by a high-frequency sequence of micro-warp jumps, with brief instants of sub-FTL speeds in between? Then the observers on the ship see a blended sequence of images of "realtime" space. This would give the screen-saver-style illusion of stars emanating from dead ahead and zooming around the ship. It wouldn't provide any color shift, though.
https://app.box.com/WitthoftResume Code: https://github.com/cellocgw
with a little uncertainty
YAB - http://blog.beemandave.com/
Can't wait for the re-mastered Star Wars 40 years edition...
but close to the speed of light.
Secondly, I also made these calculations as an excersice in high school over 20 years ago...
So, how do those Heisenberg compensators work, Scotty?
Very well, thank you!
For your first question, I'm afraid it gets rather complicated fairly fast. Essentially, when we measure things on such timescales as the expansion of the universe can affect measurements in a significant way, we stop using Euclidean geometry. Using a non-Euclidean metric, we can correct for the effects of the expansion of the universe.
We already have precise data on the expansion of the universe, which were derived from specific experiments designed to measure that (one good example is supernovae, which are known to always shine at the same brightness, thus allowing us to use their apparent brightness and redshift to calculate the expansion coefficient), as well as laws that fit the current data. With that in mind, it becomes fairly straightforward to correct for the expansion of the universe and calculate that no, those objects aren't moving faster than light.
For your second question, the answer is still that no, you wouldn't be going FTL and you wouldn't be able to "say easily the universe speeds past you". To make an example that may make more sense, take the Earth. Say you decide to walk in a straight line from New York to Tokyo (let's ignore the fact you can't walk on the sea) and measure the distance. You can then calculate the time it'd take for light to cross that distance. That's the fastest you can go using conventional movement.
Warp drives would be akin to boring a hole through the Earth so you go straight from NY to Tokyo, the crust and mantle be damned. It's obviously much harder, it takes a lot more energy, but once the bore's done, you can make the trip markedly faster. If you were to again do that trip at the speed of light, you'd get a time shorter than your last measurement. Are you going faster than light? No, of course not! You're using an entirely different path, but one which happens to be faster than anything you could do if you were constrained to "conventional" movement.
The distance between two stars is mostly fixed and is fully known: that's your movement on the Earth's surface. A warp drive allows you to discover a new path: that's your movement through the Earth. Sometimes a wormhole is also pictured as a hole through a 2D sheet which is folded on itself, with the 2D sheet representing space.
It's a fancy concept which we're not even sure is possible, but GR doesn't preclude it, so obviously people have been running with it!
What you're missing is the measurement of frequency that allows position to be calculated. That depends on relativity, but I can't remember whether it's special or general relativity. Look up " The Mossbauer Effect". It's not done with simple triangulation.
I think we've pushed this "anyone can grow up to be president" thing too far.
The Mossbauer effect is for gamma rays, x-rays, and "nuclear events". It doesn't preclude classical physics from use in GPS satellites at all. The frequency change from the Doppler shift is the only real difference to be calculated between relativistic and classical; hardly a game-breaking calculation.
Here's a paper from 1996 pointing out that:
The pseudorange measurement can be regarded from two points of view. On the one hand,
pseudorange is simply range, once the clock offsets are removed. As described in the previous
section, the ranges measured by a moving observer are foreshortened by the (gamma) factor. For an
SV speed of 3.87 km/sec, (gamma)-1 is 8.33x10^-11". The range is typically about 30,000 km. The error
incurred neglecting the (gamma) factor is 30,000 km multiplied by 8.33x10^-11" - that is, 2.5 millimeters.
Close enough for government work.
Lest you think that 2.5mm is a big deal, the US Government GPS site says:
Higher accuracy is available today by using GPS in combination with augmentation systems. These enable real-time positioning to within a few centimeters, and post-mission measurements at the millimeter level.
Clearly other people posting about nanometer accuracy in GPS would be flabbergasted to find out that GPS is not the shining beacon of accuracy they were led to believe.
I need time to process it, but thanks for the answers!
I describe what FTL is like in en.wikipedia.org/User:Teknopup kinda like witnessing the souls of the tormented slip past your spaceship window
What you're missing is the measurement of frequency that allows position to be calculated. That depends on relativity, but I can't remember whether it's special or general relativity.
It's both. There's the gravitational redshift (GR) and the change in frequency due to the relativistic Doppler effect (SR) (which includes time dilation in the moving source). Both these effects are accounted for if you employ the Schwartzchild metric for a spherically symmetric gravitational potential as GR is a generalization of SR.
If I can be modded down for being a troll, can I be modded up for being an orc, or a balrog?
wrong, that's only a point of view. the object is moving faster than light in our reference frame, get over it
The universe is about 13b years old and we can see objects that are over 40b ly away from us. Of course ftl is possible, otherwise that could not have happened.