Can you confirm the value of the g-factor for the spinning electron in H1?

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The discussion revolves around calculating the g-factor for the spinning electron in hydrogen (H1) using classical physics. The mechanical orbital angular momentum and magnetic moment are defined, leading to the conclusion that the gyromagnetic factor γ is derived from the charge-to-mass ratio. It is noted that the classical expectation of a g-factor of 1 does not match the experimentally observed value of approximately 2.0023, highlighting a discrepancy that necessitates the g-factor's definition. The classical radius of the electron is mentioned but clarified as not relevant in the calculations. The conversation emphasizes the need to reconcile classical and quantum mechanical interpretations of angular momentum and magnetic moments.
bobie
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I am studying the angular moment(s) in an atom of H (1s) in the classical model, can you help me understand some obscure points :
The mechanical orbital angular moment of the electron in 1s is L = mvr J*s:

(m) 9.11*10-31 *(v) 2.1877*106* (r) .52918*10-10 = 1.0546*10-34 J*s = h/2π,

the magnetic moment is μ = qvr/2 J/T:
1.6*10-19*(v) 2.1877*106* (r) .52918*10-10 /2=9.274 *10-24 J/T

first problem : this is the exact value of Bohr magneton μB (= qh/22πm), not of μ

The gyromagnetic factor γ (http://en.wikipedia.org/wiki/Magnetogyric_ratio) is the ratio μ / L : γ = qvr/2 *mvr = q/m2 (J/T / J*s =1/s*T) = 1.7588*1011/2 radian/s*T, γ = 8.79*1010 r/Ts
For the spinning electron wiki says:
As mentioned above, in classical physics one would expect the g-factor to be ge=1 ...(whereas it is 2.0023..., γe = 1.76*1011: q/m 1.7588*ge/2= 1.01169)
second question: how do I verify g=1, shall I take into account the electron classical radius 2.81*10-15 m* 9.11*10-31 kg and what speed?
Thanks for your help
 
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What are you asking here? The definitions that you gave for L and μ are the classical definitions Using that definition the gyromagnetic ratio is just the charge to mass ratio (divided by 2). that relationship is not realized experimentally hence the need to define the g-factor that measures the discrepancy between the classical result and the observed value. The classical radius of the electron doesn't show up anywhere in either the classical or the quantum calculations.
 
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dauto said:
What are you asking here?

hence the need to define the g-factor
The classical radius of the electron doesn't show up anywhere in either the classical or the quantum calculations.
In the article I quoted there is :
γ which is the ratio of the orbital momenta μ / L in H1 ( L = 1/2π and μ =q/2m).

γe which is the ratio ofbetween the electron "spin" angular momentum Le= \pm1/2 h/2π = h/ 4π, and magnetic moment μe/Le
and ge, the g-factor , the experimental factor that multiplies the expected classical, theoretical value of ye by 2.0023, if I got it right

The value of L in γ is mvr, where r should be the radius of the orbit in H1, Bohr radius
Isn't it so?
 
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