If space is expanding how can the electrical properties stay constant?

AI Thread Summary
The discussion centers on the implications of an expanding universe on the constancy of fundamental physical constants, particularly the fine structure constant. It is suggested that the fine structure constant, which depends on electrical charge, the speed of light, Planck's constant, and the permittivity of space, may not be constant over time. Experimental data indicates that one or more of these constants could change, potentially leading to variations in the permittivity of space. This raises questions about the constancy of the speed of light, with some Australian experiments proposing that it may be slowly changing. However, these findings are not yet firmly established and lack verification.
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if space is expanding how can the electrical properties
stay constant?
 
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It is believed that the fine stucture constant is not a constant. That is, it changes over time. This is not firmly established but there are some good indications (i.e. experimental data). Why would that interest me, you wonder?
Well the fine structure constant depends on 4 other constants:
- e: electrical charge
- c: speed of light
- h: Planck's cst
- e0: permittivity of space

[alpha]=e2/2e0hc

So if the fine stucture cst changes over time, one or more of these "constants" has to change. Since it is probably the permittivity of space that changes your question would be answered: they don't...
 
then i must be confused ,i thought that the 2Ps, governed
the speed of light ,if one of them is changeing how
can C be constant?
 
Like I said: this is not firmly established. There are also (Australian) experiments suggesting that the speed of light is not constant in time, but in fact slowly decreasing (or was it increasing). The problem is that there are no checks for these experiments yet.
 
thankyou HEUMPJE
 
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