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Center of universe

  1. Jul 15, 2010 #1
    I am not a scientist. Just a normal 52 year old.
    One question I have is - If there was a Big Bang,there has to be a place
    where it started though I've never heard anyone talk about it.
    Personally, I think there may be a Black Hole there.
    I have some stuff on Black Holes but that can wait.
    ??
     
  2. jcsd
  3. Jul 15, 2010 #2
    You have to remember that the big-bang wasn't just the creation of matter/energy; it was also an explosion of the dimensions of space and time themselves. The big-bang didn't occur in any particular "location" in space, because the big-bang gave rise to space itself.

    Consider a "flatland" analogy: you live in a 2dimensional universe, there is only forward-back, and left-right. You also live on the surface of a balloon. The big bang, is when the balloon first began to expand from an infinitesimal point; at some time later, after the balloon has expanded, you try to figure out where the big bang "happened" i.e. the center of the universe. To do this, you look at a much of markers which are fixed in place, because the universe is expanding, it must be expanding from the 'center'--so where-ever things are expanding FROM is the center. On the surface of the balloon, however, every point is moving away from every other point at the same rate (imagine drawing something on the balloon, and blowing it up--it all stretches out evenly)--which shows that there IS NO center.

    Astronomical observations show us that every location in the universe is basically equivalent, that can be interpreted as meaning that either there is no center, or every point in space is the center.
     
  4. Jul 23, 2010 #3
    The Big bang happened everywhere.

    Imagine a very long rubber sheet, and part of that rubber sheet is the observable universe (in 3d) and now stretch it from all directions to mimick the expansion. The expansion occurs in every part of the rubber sheet.
     
  5. Jul 30, 2010 #4

    bapowell

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    It might be useful to point out in this thread that when cosmologists use the term 'big bang', they are not referring to the initial moment of expansion, ie they are not discussing the initial singularity. Clearly the nature of the initial moment lies outside the regime of validity of current theories. What cosmologists mean by 'big bang' is really the model that describes how the universe evolved from a hot, dense, early phase; the big bang model refers to the expansion and concomitant cooling of the universe.

    To argue against the validity of the big bang theory on the basis of the existence of singularities or the violation of energy conservation is a gross misunderstanding/misinterpretation of the theory.
     
  6. Aug 2, 2010 #5
    It's theorized there was no "place" at the moment of the big bang...if it happened, no time nor space existed...that's what popped into existence perhaps from some type of quantum fluctuation...but as Crowell mentions, we have no real theory for that moment itself..only the evolution which began immediately after.

    Very unlikely; black holes suck things in while the big bang blew up from "nothing" and as it did so created space and time and maybe gravity and energy (radiation).....It is thought that the big bang and black holes, the only singularities given much credence in current theories, are fundamentally different....the big bang having zero curvature and black holes virtually infinite curvature (Weyl curvature)..

    For other views of the early universe search here or Wikipedia for titles like Verlinde or Jacobsen or Ekyprotic or Causal Dynamic Triangulation
     
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