12 questions linked to/from Is the Fine Stucture constant constant?
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### What is the proof that the universal constants ($G$, $\hbar$, $\ldots$) are really constant in time and space?

Cavendish measured the gravitation constant $G$, but actually he measured that constant on the Earth. What’s the proof that the value of the gravitation constant if measured on Neptune would remain ...
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### Do the laws of physics evolve?

Hubble's constant $a(t)$ appears to be changing over time. The fine stucture constant $\alpha$, like many others in QFT, is a running constant that varies, proportional to energy being used to measure ...
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### Why does the fine-structure constant $α$ have the value it does?

This is a follow-up to this great answer. All of the other related questions have answers explaining how units come into play when measuring "universal" constants, like the value of the speed of ...
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### Is the fine structure constant actually a constant or does its value depend on the energy scale?

The value of the fine structure constant is given as $$\alpha = \frac{e^2}{4\pi\varepsilon_0\hbar c} = \frac{1}{137.035\,999..}$$ It's value is only dependent on physical constants (the elementary ...
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### Can the cosmological constant change with time?

This post is a specialization of the post: Can the proportion of dark energy change? Can the cosmological constant change with time? If so, is there a measurement of this evolution up to now, and ...
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### The fine structure constant - can it genuinely be a random variable?

The question Does it make sense, and are there physical reasons to think about the fine structure constant as a (very concentrated) probability distribution rather than a single real number? The ...
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### Was Planck's constant $h$ the same when the Big Bang happened as it is today?

Was Planck's constant $h$ the same when the Big Bang happened as it is today? Planck's constant : $$h= 6.626068 × 10^{-34}\, m^2 kg / s,$$ $$E=n.h.\nu,$$ $$\epsilon=h.\nu$$
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### Big bang red shift verification

So I have read on proofs for the Big Bang theory as it appears to be a bit far-fetched to me (the layman). I mean, definitely there is some genius mathematics behind the fancy yet inaccurate ...
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### If Fine Structure Constant in not uniform in space what would that imply for cosmic background?

Recently J.Webb submitted paper which has extraordinary claim - that Fine Structure Constant is different in different directions in space! He (with others) measured $\alpha$ using quasar spectrum ...
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### Do we regularly measure and update our physical constants (By using the LHC)?

This question is motivated by sheer curiosity. I certainly do not expect that the free parameters we use in the standard model have changed in value since we started measuring them with a "modern" ...
### How does the fine-structure constant $\alpha$ vary on cosmological scales?
The observations of quasar absorption spectra show that the fine-structure constant varies on large scales. I know that $U(1)_{EM}$ coupling constant $\alpha$ depends upon the coupling constants of \$...