Intrinsic Action  (Spin)

 

According to the best available measurements

[Dehmelt, Physica Scripta T22, 102 (1988)],

an upper limit to the radius of the electron is

10-22 meters (it could be zero !).

 

If all its charge & mass were concentrated at this

distance, the outer surface must move at  1010 times

the speed-of-light to produce the measured values

for its angular momentum & magnetic moment !

 

 

Clearly this is an INTRINSIC and not a mechanical property.