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Universal Expansion

  1. Jul 26, 2005 #1
    As far as I know it's generally accepted that the entire universe is expanding; however, I recall hearing or reading that as far as we can observe, it is expanding faster than the speed of light.

    How is this possible? Assuming that it is in fact expanding faster than the speed of light, of course. I'm not sure, but I'm pretty sure I remember hearing that somewhere.
  2. jcsd
  3. Jul 26, 2005 #2


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    You will hear from conventional cosmologists that the universe can expand so fast that there is no problem with any observed expansion that is apparently faster than the speed of light. If you'd like the grand tour, just be persistent and it will be forthcoming.

    My personal view of physics contains an alternate route, branching at the distance/redshift relationtionship often attributed to Hubble, but never embraced or endorsed by him. Namely, the concept that the universe must be exploding because the farther galaxies are, the more they are redshifted.

    It is entirely possible that light can be redshifted by travelling long distances, interacting with transmissive media etc, etc. Hubble was open to this - more recent folks are not.
  4. Jul 26, 2005 #3
    I'm not quite sure what you mean by this...?

    I guess I'm not too sure on how we can measure universal expansion in the first place though.
  5. Jul 26, 2005 #4


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    Check back a few pages to here . It should clarify things. If not, there are a few other threads kicking about that deal with the same thing.
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