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We can travel faster that light?

  1. Dec 11, 2011 #1
    I'm not native English speaker so some words or phrases I say maysound strange and awkward but I hope you could get over it...according to Einsteins special theory of relativity space is relative, tiem is relative but spacetime is constant...lets say that you're travelling constant is 300 000...so if you're traveling at 1 unit through space you'll be traveling 300 000 units trough time...if you're travelling 150 000 units trough space you'll be travelling 2 units trough time...if you're travelling 300 000 units trough space you'll be travelling 1 unit trough time and let's say that that is speed of light...but why couldn't you travel at 600 000 units trough space and 0.5 units trough time? wouldn't that be more than speed of light trough space? or something even better...why couldn't we absolutely stop travelling trough space and than go trough time at infinite speed?
    Last edited: Dec 11, 2011
  2. jcsd
  3. Dec 11, 2011 #2


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    Where did you get the idea that the product of "traveling through space" and "traveling through time" is a constant?
  4. Dec 11, 2011 #3
    I tought that Einstein told in theory of special relativity that space is relative, time is relative but spacetime is constant?
  5. Dec 11, 2011 #4


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    t is relative, x is relative, but ds^2=ct^2-x^2 is constant (for 1 spatial dimension).
  6. Dec 11, 2011 #5
    Oh, thanks, I'm not physician yet, I'm only 14 xDD, so I never got to that equotation that you wrote, but I really like reading about quantum physics and things like thgat, I read Brian Greene's The fabric of the Cosmos few times and I found it actually quite easy to understand and to read...at least understandable things xDD...
    I've gotta one more question...lets imagine that some dude buys himself a ultra fast car, that can go near the speed of light...car like any other has lights and he turns them on...Einstein told that he will see light going at the speed of light in relation to him, but lets say that his GF is looking at him, but she is standing outside the car, she stands still on ground, Einstein told that light from car's lights will go at the speed of light in relation to her, even doe that he is going almost at the speed of light, they meassure the same thing for that light beam (he and light beam are going in same direction)...so can you explain it to me if is there any logical explanation? And do I got it right?
  7. Dec 11, 2011 #6

    Vanadium 50

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    It would be a good idea to start by reading the FAQs at the beginning of the section.
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