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Can space travel fast than C?

  1. Mar 14, 2006 #1

    I was watching a video lecture by Alex Filipenko of Berkeley's Astronomy Dept. and I was shocked to hear him say that space can travel faster than C, because Relativity doesn't put contraints on the speed of space itself. Does anyone have any insight on this for me please? I'm gathering that he may have been refering to the Inflationary Epoch and space's expansion at that time, but it wasn't clear from the lecture.

  2. jcsd
  3. Mar 14, 2006 #2
    No - I think he was referring to cosmic expansion - different parts of the universe may be moving at greater than c relative to each other -
  4. Mar 14, 2006 #3
    Also special relativity (and hence the speed limit of c) holds only in local frames, not global ones.
  5. Mar 14, 2006 #4
    More replies please, these are good so far but not conclusive.

    Also, is there any theory on how fast space expanded during Inflation?
  6. Mar 14, 2006 #5


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    As far as I know, space does not travel - it simply exists - and matter and photons travel in the space. If one is referring to the movement of the 'boundary' or 'edge' of the universe or space, I am afraid we do not know.

    I can't see that saying space can travel faster than c makes any sense.

    One could also say space is at absolute zero, because it has not temperature! The matter and photons in space have temperature.:rolleyes:
  7. Mar 14, 2006 #6


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    It is entirely possible that parts of our universe are forever cut off from us because they are moving away faster than c. How are they doing this, when we know nothing can travel faster than c? Because nothing *is* travelling faster than c - the space between us and those other parts of the universe is expanding faster than c. Relativity does not preclude this.
  8. Mar 14, 2006 #7
    My idea, to be demonstrated, is that light is not travelling but it is just transported by the space, it rides the space, so the space max speed is C.
  9. Mar 14, 2006 #8
    I would think that relative to one another, two points' speed could approach 2C. Whether these two points are points in space or two objects in space, if each is approaching C in opposite directions relatively their speed would be the sum of their speeds.

    Also, in assuming space can even 'travel', space has no mass, so why not?
  10. Mar 14, 2006 #9
    It can't exist an observer that measures 2C, if he is in point A he see point B moving away at C, if he is in point B the same with A. If he is in point C he see both A and B moving at C but can't measure the relative speed of A with B.
  11. Mar 14, 2006 #10


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    one other thing, it is meaningless to conceive of a vacuum moving at any speed at all. we cannot tell the difference between a "moving vacuum" and a "stationary vacuum". this is why any inertial reference frame is just as good as any other and then why in any of these inertial frames, that the measured speed of E&M must be no different than any other.
  12. Mar 14, 2006 #11
    I smell aether in this discussion...
  13. Mar 14, 2006 #12
    I think that vacuum doesn't exist. All we measure , observe, are different forms of energy, and the space as well.
  14. Mar 14, 2006 #13


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    I was in that class with Alex, and I asked him about it. He's referring to the expansion of the universe.
  15. Mar 14, 2006 #14


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    The answer given by DaveC426913 is the correct answer. I'd like to remind all of you that speculation and personal theories are not welcome here.

    Thread closed.

    - Warren
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