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Strings and Branes, a Turnabout ?

  1. Jun 14, 2004 #1
    Strings and Branes, a Turnabout ???

    When string theory came out, it was to add one dimension to the zero dimension of point-particles. Then it was realized that in order to make the theory consistent, six more dimensions must be added to space. Then M-theory needed one more space dimension.

    Brane theory proposed the existence of any number of dimensional branes. The 6-brane, 5-branes, 4-brane, 3-brane, 2-brane, 1-brane, and 0-brane. Doesn't it look like theory is now turning around going back to the zero dimension of points?
     
  2. jcsd
  3. Jun 14, 2004 #2
    I think it is drawing our attention to a point on the brane? How shall we develope our conceptualization on the nature of the brane?

    Lets just add some clarity here in terms of supersymmetry.


    http://superstringtheory.com/people/gifs/jgates.jpg

     
  4. Jun 15, 2004 #3
    sol2,

    Is supersymmetry, according to Jim Gates, the answer to the resolution of spacetime?

    What I think is that it is the answer if and only if spacetime is static. If spacetime is dynamic, then the outcome is two distinct topologies. One for fermions and the other for bosons.

    My hunch is that the dynamic of spacetime of more than 3 dimensions is very difficult to analyze. But spacetime of 2 dimensions are representable by matrices.
     
  5. Jun 15, 2004 #4
    On the first part I would say Jim Gates gives us a way in which to percieve the dynamcial relationship of these colliding branes.

    A interesting developement of this logic would have to ask, how would a photon define this relationship for us? You point out the matrices and to me Feynmenn used this and incorporated it into his discriptors for us. But there is a probelem if em considerations are held to the brane? The logic would say to me that this feature then even though travels great distances is still describing something from the origination of that brane? Gamma ray blast.

    What becomes difficult for me is to undertanding the issue of supergravity in relations to suerpmetrical points derived from a gravitational metric point considerations. So you have this scale to consider, and we know full well the dynamcis at the early universe?

    So discriteization is based on dynamcial relationships? How and what would you use to speak on this?

    The turn around is, I speaking from the current realization of the universe as it stands now. I have pointed you backward to the brane realizations of supersymmetry. This would be consistent with the understanding of a classical discritption moving to the quantum reality of this cosmo? This would be derived fromthe equationsof metic point consideration to supermetric pooint consideration. Yet visualize in your mind plasmatic features and it's dynamics, and in hand, you have gain in realization of the issues on that brane although fluid, has raised quantum realities for us to talk about?
     
    Last edited: Jun 15, 2004
  6. Jun 15, 2004 #5
    Antonio I added your post(thread) here and have been adding corrections and other information there.
     
  7. Jun 15, 2004 #6

    In the following website given by Russell E. Rierson, at the 2nd to last paragraph of the conclusions section there is mentioned of light cones of events. And this is where we can say something about dynamic discreteness of spacetime.

    http://www.ncsu.edu/felder-public/kenny/papers/gr2.html

    The discreteness of two spacetime events come from each being found outside each other's light cones since these points or events cannot be causally connected. That is to say that spacelike separated points of spacetime can never influence each other. But, I think, we can still define a metric between these two points. This metric is just the distance between the center of curvature of one lightcone to the suface of the curvature itself. But this center is on the surface of the other lightcone. Unless the surfaces are contracted to one dimension, it is very difficult to visualize the geometries. In one dimension, the geometry is that of a Hopf ring or doubly twisted Moebius strip.
     
  8. Jun 15, 2004 #7


    One of the problems that I am encountering, is that planck length has made certains determinations in regards to the quantum nature. How would any geometrical conistancy arise out of this?

    You mentioned the light cones.

    From the turn about to the early universe you saw the one aspect of matter distinction to that early universe. Now it is not altogether clear to me, but at planck length how would the lightcone be represented?

    --------------.-----------


    Looking at the second diagram, how would you see tipping lightcones?

    We no longer look at Boromean Rings, but Hopf rings as issues in regards to entanglement? Use tipping light cones I assume we understand how matter distinctions will make themselves known?

    One way in which to view this is the back to back Klien bottle. If we asume that such a dynamical reality could exist in this cyclical nature, then how would such discrete measure speak to this? A geometrical consistancy must arise, between discreteness and continuity. In a Cyclical universe, how would you percieve this notion?
     
    Last edited: Jun 15, 2004
  9. Jun 15, 2004 #8
    Take two events A and B. Both are moving at the speed of light. This is allowed since these events have zero mass. Each event has a light cone but these cones are not spatial connected. The distance between the center of curvature of one event to the surface of the other is one Planck length. Each event does complete a cycle within a distance of 2pi Planck length. The interlink of these cycles formed a Hopf ring. This Hopf ring is an invariant geometry of spacetime. Spacetime remains continuous but the cyclic link is quantized. Again, this link comes about because of the mutual constant attraction (existence of two constant forces: the difference of these forces is not zero although very tiny and is the force of gravity or antigravity depending which side of the minus sign the greater force is located. Moreover, the difference does not tell us how strong these forces are but we can assume that they are very strong indeed so the scalar products of these forces with Planck length give values comparable to Planck energy and Planck mass) between two spacetime points. When one point moves at the speed of light, a circular path is traced for a complete cycle. Any point of spacetime not located on this circular path is outside the light cone of this path.
     
    Last edited: Jun 15, 2004
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