Constants of Nature: The Fine Structure Constant - Why 137 ?

Transcript

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welcome to real physics this is a series

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of short clips about constants of Nature

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and today I'm talking about the fine

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structure constant why considering

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constants of nature at all because I

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guess this is there are a little two

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fundamental physics now what's

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interesting with the fine structure

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constant adds a number just a number no

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units and that's very intriguing I

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usually refer to 137 as the inverse of

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the fine structure constant and of

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course people are thinking I mean how

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did this number came about and there are

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some interesting ideas

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almost every week get an email

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explaining the French structure constant

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not all of them are interesting I think

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the most intriguing idea has been put

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forward by George gamof he suspected

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that it was related to the log of

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Direct's large numbers but this is also

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still speculation and I mean what's

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interesting is that at the very

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beginning of the universe this number

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137 would have been just one and that's

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from a philosophical Point of View kind

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of satisfying but as I said there is no

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theory behind if you want to explain it

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my recommendation is send the theory

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alone

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just to mention there are several points

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of view how you can look at the fine

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structure constant you see you can say

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it's just the strength of the electric

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interaction but more precisely it's the

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relation of the electric interaction to

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the quantum interaction symbolized by HC

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e squared over Epsilon naught the the

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electricity would be the strength of

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electrical interaction

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so by the way if quantum electrodynamics

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would be a really good theory it would

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explain that number it does not so if

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you want to know my opinion about

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Quantum electrodynamics check out this

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video I don't think it's very

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fundamental the relation to all this

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stuff of the Magnetic Moment of the

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electron but nonetheless 137 remains a

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very intriguing number and originally

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was dubbed a fine structure constant I

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think to do a Summerfield because you

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see it in the fine structure of the

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hydrogen lines and another way nice way

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to look at it is if you consider

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velocities in nature one important

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velocity is of course the speed of light

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and if you take the relation of the

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other important velocity which is the

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velocity of the orbiting electron in the

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simplest atom the hydrogen atom it's

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just 137

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speed of light divided by this velocity

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of the

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inner orbit in the in the hydrogen atom

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and this also Bears an interesting

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philosophical consequence if you want

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because it's a limit to the size of

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atoms because if you have a nucleus with

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more than 137 protons the velocity of

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the inner electron would exceed the

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speed of light which is of course not

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possible though this is something that

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has to do with how nature is built and

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certainly 137 or defined structure

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constants remains one of the most

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intriguing

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constants of nature if you enjoyed the

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video don't forget to like it and

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if you're interested in fundamental

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questions subscribe to this channel

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