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Where did we come from?

  1. Nov 11, 2005 #1
    There is something that i don't understand.Our position in space is nothing special and according to observations the universe is expanding uniformly. But, the big bang implies that the expansion started off from a very small region.So, we must be expanding in a particular direction(to the best of my understanding).My question is,using this can't we pinpoint the direction from which we are expanding or where the bigbang happened?
  2. jcsd
  3. Nov 11, 2005 #2
    The problem is that from where are it looks like that where at the center of the universe form every point in the universe looks like center but it isn't(unless you actullay are at the center the universve)It's hard to tell since most of observable universe isn't visble but we can see enough of it to know that were not at the center.
  4. Nov 11, 2005 #3
    How do we know that we are not at the center and since we know it, isn't there anyway we can retrace the steps of our expansion?
  5. Nov 11, 2005 #4
    I'am not sure if there's enough reserch to retrace the steps of our expansion.Reserch of the expansion of the universe is new(compared to the age of it) and there really isn't a center of the Universe because of how space curves.It's like asking where is the center of sphere surface.I'am not sure what whould be in between the universe.
  6. Nov 11, 2005 #5


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    Space expands in all directions and we don't think there's any center to the universe. There are a lot of threads on this issue, so I suggest a search of the forums. Here are a few threads to get you started:




    Last edited by a moderator: Apr 21, 2017
  7. Nov 12, 2005 #6
    Might it not at least be possible to have an objective inertial framework relative to the CMBR?
  8. Nov 12, 2005 #7


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    The CMBR doesn't provide us a reference frame from which to define a preferred position or a preferred direction. It does leave us the possibility of defining a preferred Lorentz frame -- in fact, it is from this frame that we define the age of the universe.
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