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Do strings move in spacetime ?

  1. Dec 3, 2004 #1
    Do strings move in spacetime ???

    If at every planck size point in spacetime there is a Calabi-Yau manifold.

    Do the manifolds move with the expansion of the universe so that the strings always have a constant vibrational pattern that determines their effect/elemental property or are the manifolds fixed in postion such that the strings change vibrational shape to accomodate movement and changing matter.

    What we see as objects moving is actually strings changing shape but at such a small scale and so fast that we only see fluid motion at a minimum of 25 frames per second.

    Does that make sense ???
  2. jcsd
  3. Dec 4, 2004 #2


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    It is a feature of continuum math that the base manifold can expand and the C-Y manifolds adjust accordingly. Think of the example of a line (one dimensional euclidian space, denoted R1) with a circle standing in for the C-Y (one dimensional sphere denoted S1). The combined space is dentoted R1 x S1 and called the cartesian product of the two. Now imagine that R1 expands; every length x between two points of it becomes, say 2x. In fact all the expansion takes place within the R1 itself, and we still have R1 x S1, no problem.

    You are roughly right about the cause of motion. Strings are not at the Planck scale but at a somewhat larger scale; Planck length is just as small with respect to a string as a string is to us. Particles are not in one-and-one correspondence to strings; the quantum wave function of the particle comes from the vibration of the string, and one string can do more than one particle because of superposition.
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