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Termial Volecity

  1. May 23, 2006 #1
    Granted, the universe is expanding, granted the rate or speed is ever increasing, but what is the terminal velocity, knowing that anything with mass can not reach the speed of light?
  2. jcsd
  3. May 23, 2006 #2


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    The 'expansion of the universe' refers to the expansion is of space itself and not the motion of masses (e.g., galaxies) within the universe. Perhaps someone can correct me here, but I don't think there is a known maximum expansion rate (considering we only recently discovered that the expansion is accelerating). During the inflationary period immediately following the Big Bang event, space expanded much faster than the speed of light. The current expansion rate is expressed by the Hubble Constant.
  4. Jun 12, 2006 #3
    I think you're right

    I'm no expert, just an amateur that watches shows like Nova and reads posts like this, but when I was 12 years old (and I'm on;y 33), people were still fiddling with the idea that the space-time was static except for warping caused by gravity, there were still people arguing that Black Holes don't exists, and many people thought the universe expanding or collapsing was only an expression of inertia vs. gravity.

    Then Hawking started talking about the space-time structure changing, and more recently, that the universe is actually expanding, which if true is proof that the "fabric" of the universe is expanding, not just the matter within it, 'cause matter don't just accelerate for no good reason.

    I doen't know of any reason to say that no-matter realities, such as changes in the space-time curvature are limited to the speed of light. To the contrary, the force gravity seems to instantaneous (correct me if I'm wrong) and this mind boggling "sppoky action at a distance" of quantum physics seems to transmit "information" faster than the speed of light over, supposedly, infinite distance (I still think they need to stop calling it "information" which makes it sound like the electrons are talking to each other)
  5. Jun 12, 2006 #4


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    These are not correct. Current theories on gravity does not make it instantaneous. The EPR-type experiment has been exhaustively discussed in the QM forum and has been clearly described to not transmit information faster than the speed of light.

    Please do a search in the relevant forums to correct your understanding on these.

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