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Why 1 dimensional discrete space?

  1. Apr 22, 2003 #1


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    It seems that the idea of space being made out of some 1 dimensional fundemental entity is popular these days. Not only does string theory propose the structure of space to be 1D loops, but Loop Quantum Gravity proposes a lattice built of similar 1D loops. What is the advantage of this? I know that if you were to shake a string, the vibration would travel down the string at the speed of light, so as to not violate SR and avoid the point particle. But it seems one could apply the same logic to a fundemental loop of 3 dimensions.

    So what is the practical benefits of a 1D entity over something of extended dimensions?
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  3. Apr 22, 2003 #2


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    Well string theory begat brane theory, where the elements are of higher dimensions.

    IIRC, physicists around 1960 tried to develop a field theory in which the electron was a little ball. It didn't work. Apparantly the element has to be "of measure zero" in the relevant space in order for the theory to even approximately converge.
  4. Apr 22, 2003 #3


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    One dimension??
    From all I can find, String Theory requires at least 10 dimensions, and in some cases more. See one "explanation" at:


    It does remove any necessity for infinities, which I don't believe have any place in Cosmology anyway. Just personal opinion, but I can't buy String Theory either.
    Last edited: Apr 22, 2003
  5. Apr 22, 2003 #4
    Maybe next a fractal dimension <1?

    In 10 dimensional space, strings are the fundamental 1-D constructs of the string theory.

    Also, aren't (quantum) probabilities often composed of singular (0-D) values?
  6. Apr 23, 2003 #5


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    I'm talking about the strings, which are 1 dimensional entities.
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