Hello all.(adsbygoogle = window.adsbygoogle || []).push({});

I only have a few posts here so I am somewhat new to the forum. I have been reading a number of the posts though and I am favorably impressed by many of the responses. I am also somewhat new to LaTex so please forgive my mistakes with it.

I am interested in learning more about the fine structure constant [tex]\alpha[/tex], where

[tex] \alpha = e^2/\hbar c \sim 1/137 [/tex]

e = elementary charge

[tex] \hbar = h/2\pi [/tex], h is Planck's constant

c = the speed of light in a vacuum

Another way of writing the fine structure constant is

[tex] \alpha = \frac{\hbar/mc}{a_0}[/tex]

m = mass of an electron

[tex]a_0[/tex] = the Bohr radius

I understand that the fine structure constant is dimensionless and is one of those enigmatic fundamental constants that pops up in the study of nature.

I further understand that it is used in electrodynamics, how? Where else is it used?

What are the leading explanations as to why it exists and why it might take on the value it has?

Does it relate to other numbers like Pi, e, the number of spatial dimensions in the universe?

What do you think?

John

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# Fine structure constant

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