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Expanding universe and light detection

  1. Nov 7, 2009 #1
    Sorry if this question has been reproduced elsewhere.

    If the universe expands greater than the speed of light, c, will a light ray from a distant object never reach us? Lawrence Krauss gave a nice presentation and commented about this, but this has thrown my nose out of sorts because I think light will reach us irregardless of frame speed, even a frame traveling greater than c oppositely.

    Thanks for reading.

  2. jcsd
  3. Nov 8, 2009 #2
    The velocity of a distant object is given by Hubble's law
    [tex]v=H_0 d[/tex]
    where v is velocity, d distance, and H is a constant. The distance at which v=c marks the Hubble limit--more or less the event horizon--beyond which we cannot be causally connected. No, light will not reach us.
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