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Big Bang Expansion Creates Planets?

  1. Jul 16, 2015 #1
    If I understand what the BB Theory proposes, all the universe was originally confined to the size of something very small, like a dot or an atom. This small dot or atom or whatever was said to explode, although some say there was no explosion in the sense of a bomb going off, but would be more accurately described as everything began to expand like raisons going away from each other as would happen when you bake raison bread in an oven.

    If I am stating the theory correctly, it would appear that whatever caused this expansion to occur caused the raisons to separate in a specific direction, i.e. away from each other, hence the expansion.

    If I am understanding the BB Theory, whatever force at the beginning that caused this expansion of material to occur is the only force being described, maybe roughly described as the buckshot that would come out of a shotgun when the trigger was pulled.

    So the question is, the trigger has allegedly been pulled, the particles are now expanding in a specific speed and direction. Newton said "...an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.'

    What 'unbalanced force' is proposed to act upon these elements that would cause them to change their direction of separating and expanding and to then come together to somehow create planets?

    Thanks - Gary
  2. jcsd
  3. Jul 16, 2015 #2


    Staff: Mentor

  4. Jul 16, 2015 #3


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    Basically, quantum fluctuations made it so that some regions were a tiny bit more dense than other regions. Gravity caused the denser regions to collapse.
  5. Jul 16, 2015 #4


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    Yes, quantum fluctuations in the primordial universe resulted in uneven energy distribution [density gradients] across the then observable universe which ultimately permitted gravity to initiate large [and small] scale stucture formation.
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