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Old idea?

  1. Jan 11, 2005 #1
    There was a section in Greene's book that actually helped me form a curious idea about the origins of the universe and I wanted anyone's thoughts on it. If there was only one Big Bang, then shouldn't there be a concentration of matter/gas in the region of the center as everything spreads in all directions?
  2. jcsd
  3. Jan 12, 2005 #2
    which centre? the universe apparently does not have a centre. strange, I know. it also does not have an edge. crazy stuff
  4. Jan 18, 2005 #3
    which centre?

    The center of the "explosion."
  5. Jan 18, 2005 #4
    The "Big Bang" was not an "explosion"
    just the earliest part of the expansion that started a little before the origin of the CBR we can still see today.
  6. Jan 19, 2005 #5


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    Welcome to Physics Forums, Mr Euchre.

    Like RandallB said, the Big Bang was not an explosion of stuff into space. (the "Big Bang" is a poor, misleading name...but a catchy one)

    The Big Bang was the rapid expansion of all space. Essentially, the Big Bang happened simultaneously everywhere in the universe. We do not see concentration of matter toward any center or any preferred motion of things away from any center. There is no center or edge to 3D space.

    With the rapid expansion of all-space, the energy in it cooled...eventually enough for atoms to form and then stars, galaxies, & planets...throughout the universe.
  7. Jan 20, 2005 #6
    Do you have any suggestions for a more accurate descriptive name?

    Doesn't this kind of suggest that there is some kind of void into which space is expanding? (i.e Expanding relative to what?)

    If we say that it's merely expanding relative to itself, then how would that be any different than imagining that it started out extremely large (possibly infinite) and then there was the Big Ting? Like a gong hitting a bell, only the gone hits the entire universe at once (every point in preexisting space simultaneously). Forget about SR, nothing was moving prior to the Big Ting so everywhere in the universe was in the same frame of reference so it makes sense to talk about a simultaneous Ting.

    The Ting was so powerful that the entire universe burst into a state of ultrahigh temperature. As it cooled it condensed and everything in it started shrinking. How would that be different than an expanding universe?

    I think that the only difference is in where the energy goes. The idea is that when things expand they cool, so the expansion supposedly explains energy conservation. In the Big Ting model the energy would need to somehow radiate away from the universe like the ringing sound leaves a bell.

    Although, if string theory is correct, then we have the explanation that gravity waves radiate away from the universe carrying with them the dissipative energy and the ringing of the Ting.

    I believe in the Big Ting model myself. :approve:
  8. Jan 21, 2005 #7


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    Yeah, personally, I think the word "expansion" also has the wrong connotation for what the universe is doing....but such are the limitations of our language.

    No immediate response to this...although it reminds me of some of the discussions in the general astronomy forum (marcus?) about defining the Big Bang "singularity" (a point vs. a uniform/undifferentiated state of spacetime)

    So would you expect to detect a temperature ramp up in the early universe? (at a time less then 10e-43 seconds perhaps?)

    Shrinking matter & energy? (ongoing)
    Seems like this would mess with gravitational & quantum effects in a way that we don't see.

    It's just one ting after another. :biggrin:
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