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Eleven dimensions, too small or too big?

  1. Mar 28, 2009 #1
    I am quite familiar with 11-dimensional string theory and with the concept that the other seven dimensions outside of the four we can perceive are, in theory, curled too tightly (meaning too small) for us to see.

    However, is it possible that instead of being too small, they are too large?

    Assume, for a moment, that there exists an eleven dimensional hyper-sphere (hyper-space) and its surface is a zero energy sheet. A random fluctuation occurs on a portion of the surface and the sheet separates producing a negative and a positive energy bubble each with four dimensions. Within each bubble a tremendous amount of energy would be released (i.e. a Big Bang). The rest is history.

    Further, imagine that each particle (string) within those bubbles (branes) is still “connected” to the hyper-sphere. Companion particles would be connected through the hyper-sphere whether they are an inch or light years apart. If you then change one of the properties of one of the connected particles, that change would be immediately “transmitted” to its companion particle which would then exhibit the change as well. It would help explain the entanglement phenomena.

    There was a theory (Broglie-Bohm Pilot Wave Theory) proposed by Louis de Broglie and later, by David Bohm that, basically, advanced the idea that there is a guiding wave (pilot wave) that transmits the change between companion particles and would have the properties of being faster than light and would not lose any of its energy regardless of how far it traveled.

    So if indeed, particles are connected through hyper-space, they would exist virtually side-by-side in hyper-space regardless of how far apart they are in our universe. It would do away with the issues of the Pilot Wave Theory (i.e. faster than light and no loss of energy over any distance).

    Another thought on the hyper-sphere idea. If our universe was the positive bubble would the negative bubble have had its own Big Bang and would it be composed of ant-matter? It would explain why we see so little anti-matter in our universe even though, statistically, our universe should be half and half.

    So am I totally off base or is there some merit?
  2. jcsd
  3. Mar 28, 2009 #2


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    You seem to be mixing at least two different interesting speculations here. I've thought about them too, So it would be useful maybe for people to deal with them separately.

    1) String dimensions remain connected while 3D expands: It would seem a natural part of the 6D compactification story and CY spaces that it is essentially the same little space at every location in the 3D realm. So as you say, every point of space remains non-locally collected. Or rather. lacking in local separation.

    The compactified dimensions would be in effect a timeless realm, and the 3D world would have the accumulating history where events take time (or at least, the time of events in the compactified dimensions would be of the planckscale).

    But then I don't quite get how this lack of separation would be the case if you want to argue that the extra string dimensions are instead the larger space. Oh, I see you are talking faster than light pilot waves. This would give you the same outcome but seems to introduce more mechanism than we would want.

    2) Your second hypothesis is about a symmetry of universe creation: this is a common speculation, is it not? I don't like that kind of simple symmetry breaking because it is unrealistic in my book.

    Symmetrical symmetry breakings are a 50/50 deal and unstable. Whereas asymmetrical symmetry breakings (as in a phase transition) are more like 99/1 deals and are stable (having become as broken as possible).

    A key asymmetrical symmetry breaking in the formation of our universe, for example, was the "mattergy"/gravity split. Equal amounts of each. But two things are produced which seem utterly unalike.

    The CPT matter-antimatter tiny discrepancy seems to be explained by a handedness in gauge symmetry breakings. The handedness has been observed, but I am not sure if it has been accounted for at the theory level (as actually a platonic property of the gauge symmetries). Perhaps someone has the answer to that?

    So two good questions I think.

    1) Does the string approach (compactified and/or hyper-connected) say that there is effectively no distance between two points in the universe for certain kinds of communication? Entangled events in our world could be two ends of the same tiny and unseparated resonance in the string world.

    2) What is the plausibility of a symmetrical symmetry breaking (along the lines of positive and negative charge) for whole universes?

    This kind of creation event would obey the first law of conservation. Which would be why some would prefer it. But it could be argued that the second law of dissipation is the more fundamental. And so another group of us would prefer creation events that are asymmetrical symmetry breakings.
  4. Mar 28, 2009 #3
    I was under the impression that large extra dimensions could be ruled out. For instance, if you consider the one-dimensional infinite potential well and add just one compactified extra dimension, the first observable change to the original problem occurs at energy scales that are much higher than we can currently observe. If, instead, the extra dimension is large, there are shifts at currently observable energies that we certainly do not see.

    Perhaps this can be accounted for if we add more than one (i.e. six) large dimensions.
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