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Matter in Space-time

  1. Sep 7, 2010 #1
    Just curious. How come we say that at the moment of the bb space and time started to expand, and within this BB contained all the matter of the universe. But we see matter as creating curves in space time creating gravity. Wouldnt this imply that matter came after space time as it is changing it? I am having a hard time explaining it but you are smart people and can figure it out.lol
  2. jcsd
  3. Sep 7, 2010 #2


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    Matter and energy are equivalent where gravity is concerned.
  4. Sep 8, 2010 #3
    There are two basic types of particles. Fermions and bosons. Fermions are the particles that people normally think of when you talk about "matter" and bosons are the particles that people normally think of when you talk about "energy."

    However, it's possible to change particles from fermions to bosons and bosons to fermions, and from the point of view of a physicist, they really are the same thing.
  5. Sep 13, 2010 #4
    Let me trty and explain my question using the trampoline idea. The trampoline is space time and all matter causes curves on the trampoline. Would this not imly that trampoline was once flat and matter was introduced later. If the trampoline and matter were created at the same time wouldnt they be woven together, and not change the curvature of the trampoline?
  6. Sep 20, 2010 #5


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    The problem is that your assuming that there was NOTHING there before the big bang. In my understanding of the big bang, all the matter and energy of the universe was already concentrated in a single point, and possible space itself too. Take your trampoline and unhook all the springs. Then bring the outer edges all together to make something akin to a big bag. Thats kinda what it was like. One big curve.
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