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Fractal Sphere

  1. Sep 25, 2006 #1
    I have heard of such idea:

    A sphere of fractional dimension 0<s<1 is understood as a probability sphere with probability s to have an electron at a certain position

    for example the volume of the sphere S^{n-1} in \Re^n has volume

    Vol(S^{n-1})= (2\Pi^{n/2})/(\Gamma(n/2)

    and we can apply the result to non-integer values of n

    Anyone have heard of this idea and show me the link for further information? :confused:
  2. jcsd
  3. May 8, 2007 #2
    I have been searching for the same thing, and a few places say that it is given by:


    for any dimension, even fractional ones, but I am trying to find a way to prove it myself, perhaps using integration with respect to the Hausdorff measure (since it recognizes non-integer dimensions). And just a note- the formula you gave is actually the area measure of the unit S^{n-1} sphere, the volume of the unit S^{n-1} sphere is actually:


    **Note that the denominator can be rewritten {(n-1)/2}\Gamma((n-1)/2)}.
  4. Jul 23, 2007 #3
    The proof for integer [tex]n[/tex] is simple and done by induction. It could be found for example in

    Chapter 5.9 of W Fleming: "Functions of Several Variables", Springer-
    Verlag 1977

    We generalize [tex]n![/tex] to [tex]\Gamma(n+1)[/tex] and the formula is obtained.
    My problem is the physical aspect. What is the physical mean of a "fractional sphere" and could it possibly be related to "probability sphere" in Quantum Mechanics?
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