Faster than light electron spin

AI Thread Summary
The discussion revolves around the concept of electron spin and its relation to speed, with participants exploring the theoretical implications of electron rotation exceeding the speed of light. Calculations using the classical electron radius and the reduced Compton wavelength are suggested to understand angular momentum better. There is speculation about the electron's charge radius being similar to that of the proton, despite differences in mass and magnetic moments. Participants encourage calculations for fun, focusing on the implications of these theoretical values. The conversation highlights the complexities of relating classical physics concepts to quantum mechanics.
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I understand that we are not to think of an electron literally spinning on its axis because the equatorial speed would far exceed the speed of light. However, just for fun, I've been trying to find out just what the speed would be to make the numbers come out to agree with the observed angluar momentum. I've seen 100x the speed of light and 10^32 radians/s. But at what polar radius is that? Anyone have more info on this?
 
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The theoretical radius of the electron is 0. But people often use the classical electron radius http://en.wikipedia.org/wiki/Classical_electron_radius
Note that as you get smaller, the problem gets worse because the moment of inertia goes as R^2, and velocity at the edge of a rotating body goes as R.
 
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Your question is "just for fun", so go ahead and do the calculation and do not worry about light speed. Use the reduced Compton wavelength for the radius. What do you get?
 
liometopum said:
Your question is "just for fun", so go ahead and do the calculation and do not worry about light speed. Use the reduced Compton wavelength for the radius. What do you get?

Just for fun I predict electron 'charge radius' is the same as that of proton, and since proton has smaller magnetic moment I bet it's spinning with less speed than electron.
 
My focus is on the Compton radius (Compton wavelength divided by 2 pi). The radii of electrons and protons will not be the same due to the difference in masses.

I suspect you will find that the spin velocities are identical.
 
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