E^2/((h/(2*pi))*c)=1/137

[sanctus]

This is quite stupid question I guess, but if trying for half an hour doesn't give me what I looked for.

One caan get very easily e^2/(h/2*pi)*c=1/137 in the gaussian units.

How is the calculation done in SI-units (=MKSA units)? i tried with the conversion table in the J.D. Jackson, but never got to the result.

[Erasmus00]

This is quite stupid question I guess, but if trying for half an hour doesn't give me what I looked for.

One caan get very easily e^2/(h/2*pi)*c=1/137 in the gaussian units.

How is the calculation done in SI-units (=MKSA units)? i tried with the conversion table in the J.D. Jackson, but never got to the result.

 

Your forumla for the fine structure constant e^2/((h/2pi)*c) isn't quite valid in SI units. You need a factor of Coulumb's constant (1/(4pi*epsilon)). Working that out gives you the 1/137.

-Will

[infamous]

Your forumla for the fine structure constant e^2/((h/2pi)*c) isn't quite valid in SI units. You need a factor of Coulumb's constant (1/(4pi*epsilon)). Working that out gives you the 1/137.

-Will

 

Thats exactly the reason why I choose to use the cgs/esu form of units. Much easier to deal with, at least from my perspective. The problem occurs when trying to use the SI unit which defines (e), it is the elementary charge measured in electromagnetic units. When using the cgs/esu figures, (e) is calculated in electrostatic units which work quite nicely with planks constant (h/2pi) times c when all units are defined in cgs terms.