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I have a Question about the big bang theory

  1. Jan 31, 2005 #1
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    So. how can all the matter in the whole universe be compressed into one small little ball. all the matter in the UNIVERSE. it seems impossible. but im sure alot of u guys have alot of ideas. maybe all the matter in the universe was under a great deal of force. and where the hell did the matter come from any ways. i guess that is the big question.
     
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  3. Jan 31, 2005 #2

    Chronos

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    Try asking a question without big letters and preconceptions. Welcome to PF.
     
  4. Feb 1, 2005 #3

    saltydog

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    Does that mean I can't answer? It's so interesting though . . .

    Maybe singularities are involved: Imagine a water creature never having been exposed to ice and wondering how swimming will be affected when the temperature drops below freezing (alright, I mean frozen solid). That involves a "phase-transition" (a type of singularity) and represents an abrupt qualitative change. Perhaps that's so with the Big Bang: Questions of "matter, density, and size" loose meaning across a singularity that could involve physics different from what we've been "exposed" too.

    Salty
     
  5. Feb 1, 2005 #4
    my ideas lead to : no mass = no size.
     
  6. Feb 1, 2005 #5

    selfAdjoint

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    Right after the initial moment, matter did not exist; protons and neutrons did not exist, what was present was a very high energy bound state of quarks and antiquarks, but too tightly bound to interact. The unified force bosons were all massless and bound in a BEC.
     
  7. Feb 1, 2005 #6
    what does BEC mean?
     
  8. Feb 1, 2005 #7

    JesseM

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  9. Feb 2, 2005 #8

    Chronos

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    BEC is irrelevant. As SA said, the only thing that matters is the energy level. I would only argue that even quarks cannot exist in the primoridial soup that emerged from the initial state. Push the energy level high enough, and even quarks break down.
     
  10. Feb 3, 2005 #9

    Phobos

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    As noted above, there was no matter at the very beginning. Protons & neutrons appeared a split second after the Big Bang event and atoms didn't form for another 300,000 years or so.

    So where did all the energy in the Big Bang come from? That is unknown, athough there are many speculations about it. Big Bang Theory is silent on that (it describes the universe AFTER the beginning). String Theory provides a possible explanation that is fairly popular, but it's a long way from being well proven.
     
  11. Feb 3, 2005 #10

    hellfire

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    There is indeed one explanation within the big-bang model for the origin of energy and matter, but it is a very vague one: The universe may start with (nearly) zero energy density (nearly zero energy in a finite universe). During inflation, the inflaton, a scalar field with constant energy density, accumulates energy as the volume increases. This energy is borrowed from its own gravitational potential, increasingly negative, since space is expanding with constant energy density and therefore more energy (gravitational mass) is created. I am not sure, but I think the Vilenkin model of tunneling for the origin of the universe relies on the assumption of zero-energy initial state (this is beyond my knowledge). The whole idea is a wild speculation, since we do not know what role the principle of energy conservation plays at such stage and we also do not actually know how to properly define the energy of the gravitational field.
     
    Last edited: Feb 3, 2005
  12. Feb 3, 2005 #11

    DaveC426913

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    "So. how can all the matter in the whole universe be compressed into one small little ball. all the matter in the UNIVERSE. it seems impossible."

    Personally, I think the overarching concept to hold onto is that, at the beginning of the universe, there was no matter. It was not simply compressed and under great force, it was not there at all, neither was the fabric of space. The universe was too energetic for mere matter and space to exist.

    The universe as it existed 1 millisecond after the big bang had more in common with today's state of the universe than it did with the state of the universe before that. (In other words, the really weird stuff happened in the first millisecond).
     
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