What is the Concept of a Fractional Dimension Probability Sphere?

bchui
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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:
 
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I have been searching for the same thing, and a few places say that it is given by:

\Gamma^2(1/2)/\Gamma(n/2)

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:

Vol(S^{n-1})=[2\pi^{(n-1)/2}]/[\Gamma((n-1)/2+1)],

**Note that the denominator can be rewritten {(n-1)/2}\Gamma((n-1)/2)}.
 
The proof for integer n 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 n! to \Gamma(n+1) 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?
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
If we release an electron around a positively charged sphere, the initial state of electron is a linear combination of Hydrogen-like states. According to quantum mechanics, evolution of time would not change this initial state because the potential is time independent. However, classically we expect the electron to collide with the sphere. So, it seems that the quantum and classics predict different behaviours!
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