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Where is the string?

  1. May 8, 2004 #1
    where is the string??

    Where is a string located? Is it inside a calibi-yau?
  2. jcsd
  3. May 9, 2004 #2
    I am no expert on strings, but I do believe that strings have different descriptive 'types', for instance electrons can be located in dimensions that allow them movement, but in other dimensions they are 'frozen' and there is constraint? a calabi-yau has an infinity number of configurations, when linked to the number of possible discrete volumes of space that can exist in just a six-dimensional space 'hidden' from the everyday 3-D space of everyday geometry.
  4. May 9, 2004 #3
    The unseen dimension’s small size explains why humans, or even atoms, are unaware of it. Even so, it would yield electromagnetism. And gravity, already present in the four-dimensional world, would be united with that force.

    http://feynman.physics.lsa.umich.edu/~mduff/talks/1998 - The Theory Formerly Known as Strings.pdf

    However, since the extra dimensions are compactified, we would not normally observe effects of the extra dimensions at scales larger than the compactification radius. Thus, when we measure gravity in only three spatial dimensions, we find it to be weak; we have not measured gravity in the entirety of the space that the field lines inhabit. These extra dimensions could be compactified at a length scale just below the length scales at which we have successfully measured.


    There is a transference of thinking here, when we loose sight of the reductionistic principals :smile:

    When you see, you see brane world? Brane world is adifferent level of thinking Reductionistic implication soildfy in a three dimensianl world, while out there exists this whole new set of holographical realizations?

    It's always bigger then the matter distinctions, and yet, if we were to implore this new level of thinking, what new elements would arise?

    Such an avenue of predictions like Mendeleev elements, would allow such predictions in superstringtheory(?) to identify new possible structures? New crystals?:biggrin:

    What arises out of the standard model? There must be certain determinations below planck length? What lies beneath our current realizations?

    Predictions for the Mendeleev Model
    Last edited: May 9, 2004
  5. May 9, 2004 #4


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    Strings would be everywhere, in our spacetime dimensions as well as in the compacted dimensions. Every electron and quark and so on that makes up our matter, and also the virtual particles that fill the quantum vacuum, is seen as a vibration mode of a string. Of course this is exactly where string physics has not well demonstrated itself. They claim this would be true, but their mathematical models so far can only get part way towards showing how it works.
  6. May 9, 2004 #5
    What I meant was, where are strings in relation to the Calibi-Yau? I know they are everywhere (along with the calibi-yau). But exactly where in relation to the calibi-yau?

    thank you for all your replies everyone.
  7. May 9, 2004 #6


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    They are embedded in the Calabi-Yau manifolds. They can move within it, and if it is not simply connected they can wrap around with non-trivial homotopy. It helps to think of a torus instead of the mysterious six real dimensional Calabi-Yau manifolds (3 complex dimensions - Calabi-Yaus are all Kaehler manifolds before anything else).
  8. May 10, 2004 #7
    The string theory is background dependent (that is no explanation for the spacetime itself is given,such what is it,is it quantised also?) being however very good at explaining matter.This is why some physicists believe that only a mixture of string theories with other theories which account also for spacetime itself (loop quantum gravity for example where spacetime itself is quantized being made up from tiny 'quantum loops') could really lead to a theory of everything with strings made up from those,even smaller,'quantum loops' (having Planck size).
    Last edited: May 10, 2004
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