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The metric expansion of the Universe

  1. Dec 24, 2009 #1
    I have a few questions ragerding this topic. Any help with either question is appreciated.

    Is the metric expansion subject to relativistic effects? Will we measure the expansion of space around the Milky Way to go faster than the expansion around the Andromeda Galaxy?

    How is the expansion related to the cosmological constant and Hubble's Law? Has anyone been able to derive an expression for the expansion?
  2. jcsd
  3. Dec 25, 2009 #2


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    It is an extremely relativistic effect, as it is mostly "speaking of normal things in unfamiliar coordinates". IOW: outside Gerneral Relativity, you couldn't even formulate such a concept.
    Short answer: most probably no.
    Longer answer: You can't measure expansion locally, the concept is useful only globally, if you regard the universe as a whole.
    Hubble's law is simply another ord for expansion of space - distances increase proportional to distance.
    The cosmological constant tends to increase the expansion with time. It is a repulsive "force".
    Yes, http://en.wikipedia.org/wiki/Friedmann%E2%80%93Lema%C3%AEtre%E2%80%93Robertson%E2%80%93Walker_metric" [Broken].
    Last edited by a moderator: May 4, 2017
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