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How can all the matter in the universe start out as one point?

  1. Mar 4, 2010 #1
    i love these types of questions, however, i am a novice and the answers seem to be more complicated than they should.

    There is no way that all the matter in the universe can be contained in a single point that was held together by four forces. The symmetry of the singularity was distrupted and the four forces became released from one another giving rise to the big bang. Then, there is all this matter and anti-matter colliding with each other to release energy for inflation. But, yet, there was 1 part in one billion more matter than anti-matter. How can that be? What ever happened to symmetry? If there was symmetry in the singularity, why was there more matter than anti-matter? And how in the hell could all the matter in the universe fit in that tiny space? I get upset with these assumptions but no one seems to mind them.
     
  2. jcsd
  3. Mar 5, 2010 #2
    1. It is incorrect to think about the Big Bang as started 'from a single point'. For example, if Universe in infinite now, it was ALWAYS infinite (but more and more dense if we go back to the BB)
    2. 'point that was held together by four forces'. No, no, and no! You imagine a single point in emptry space, and forces preventing it from explosion! this is absolutely incorrect:
    * there was no empty space around
    * all space was filled with very dense *something*
    * as there was no inside and outside so pressure did not 'cause' the explosion
    * even more, pressure creates gravitation, so in fact that pressure *slowed down* the expansion!
    3. Finally, matter/antimatter disbalance. The symmetry (C, P, combined CP and T) are violated. Sakharov suggested a mechanism to create more matter than antimatter suing CP violation, but it is not enough to explain all matter we see
     
  4. Mar 8, 2010 #3
    Have you ever heard of a singularity?
     
  5. Mar 8, 2010 #4
    Flatland could you produce some evidence other than mathmatical to support the existance of singularity ?
     
  6. Mar 8, 2010 #5
    Have you ever heard that you should read a post before making a silly comment?
     
  7. Mar 8, 2010 #6
    There is no way that all the matter in the universe can be contained in a single two-dimensional or three-dimensional point, but it is possible to be contained in four-dimensional point:)
     
  8. Mar 8, 2010 #7
    no way Dude. 4th dimension is time and i don't see how time would support the inclusion of all the matter in the universe.
     
  9. Mar 8, 2010 #8

    bapowell

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    Magnus,
    If you're looking for someone to give you a satisfactory explanation of how copious amounts of matter could be concentrated into a spatial region of zero size, then you'll be disappointed. Nobody understands how to resolve this (unless they've got the UV completion of gravity and they're holding out on us!) The Big Bang is best thought of as Dmitry suggested -- not being concentrated at a single point but being spread out over an already finite (or possible infinite) region.
     
  10. Mar 8, 2010 #9
    Does that mean that the universe was already spread out as "chaos" with no information, and that the big bang is merely the conversion of no information to information. I dont have a problem with that, but i must confess that i know very little of chaos theory which may explain this very naive post.
     
  11. Mar 8, 2010 #10
    "already", "was", "conversion" - these words require the concept of time
    For example, "conversion" means "was in state A at earlier moment of time, but in different state B after that"
    It is not clear was was in the very early Universe. We even don't know the number of dimensions and how "smooth" were these dimensions (or may be they were some networks like in loop gravity).

    It is possible that close to the BB there are more then 1 time dimension, or zero time dimensions, or concept of time was not applicable at all (for example, there was no difference between different dimensions)
     
  12. Mar 8, 2010 #11

    bapowell

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    Who knows? The standard Big Bang theory does not attempt to deal with such questions. It is a description of the evolution of the universe from some hot dense early state (some time after the Planck time.) How and why this state came to be is currently not known.
     
  13. Mar 8, 2010 #12
    Thank you Dmitry and Bapowell for taking time (i mean, the 4th dimension time :rofl: ) to help me with this question.
     
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