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A few different questions and concepts

  1. Apr 15, 2010 #1
    Hey everyone 1st off this post will contain a few ideas that aren't really all that related to each other but I’m posting them together not to spam the boards. I posted them under General because the topics are literally all over the place

    Could it be possible that dark matter was left over from pre-big bang? Given the fact that it acts as the gravitational centre for many of today’s structures, it had to have come from somewhere

    What if time itself causes super symmetry breaking? Could time be responsible?

    Could it be possible that our universe was created through a 3-brain collision instead of 2? The original 2-brain collision could have created everything up to pre-inflation and inflation itself (and everything after it) was created by the 3rd brain?

    No light escapes a black hole. What would happen to the electrons of an atom within it? The electrons work off of orbital energy, this energy is a photon. Not even light can escape its pull so either atoms would be ionized given the fact that within the black hole there is a lot of photons (and energy) or, the atoms would display Bose-Einstein condensate type behaviour based off of the fact that the electrons would be stuck to the lowest energy state

    Could it also be that dark energy is space-time itself? Dark energy is seen to be responsible for the expansion of the universe and the only thing that the universe is intertwined with is space-time itself

    Could it also be that the density of the universe is responsible for its own expansion? In the early universe we didn’t have things such as black holes. Because of that wouldn't the density of matter in space be more uniform and spread out than it is now? Now, we do have black holes and other heavy things that would change the overall density of space, possible having an effect on its own expansion?

    I had one more question about the possible relationship of electromagnetism, dark matter, and gravity but I cant seem to remember it :(

    I hope you guys don’t find my questions too far out there and any possible ideas on them would be appreciated

    Last edited: Apr 15, 2010
  2. jcsd
  3. Apr 15, 2010 #2


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    Yes, either directly or a decay product of something that existed at earlier times.

    If supersymmetry isn't broken explicitly, but spontaneously, then the symmetry is controlled by an 'order parameter', typically the value of one of the fields in the theory. The field evolves in time, and so there is some sense in which time is implicitly involved in the symmetry breaking. As far as I know, time has never explicitly been utilized to break any symmetry.

    Are you referring to 'branes'? I think you are confusing this concept. Cosmologies utilizing branes (so-called braneworlds) may or may not involve inflation -- so there is no direct relation between inflationary expansion and the involvement of branes in the theory. The brane collision you speak of was popularized in the 'ekpyrotic universe' of Khoury et al, and involves the collision of two M-theory branes. These branes can be taken to have 3 infinite (or simply non-compact) spatial dimensions, in agreement with what we observer our universe to look like.

    There's little use in discussing what happens inside a black hole. Nobody really knows. Black hole solutions in GR show that time and space reverse roles inside the event horizon of a black hole.

    Spacetime behaves in response to sources of energy. One needs a source of energy to drive the acceleration of the universe. If you just have empty space (no vacuum energy), you get the static, non-gravitational world of special relativity.

    The expansion rate of the universe does indeed depend on the energy density of the universe. While it is certainly true that matter was more uniform in the early universe (before bound structures like galaxies and black holes came around), it was still more dense because the universe was smaller! As the universe expands and the uniform matter field begins to collapse into structure, we need to speak of an average density taken over some volume of space. This density was larger earlier on than it is today, and hence, the expansion rate today is smaller than it was back then.
    Last edited: Apr 15, 2010
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