Measurement accuracy or variation

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SUMMARY

The discussion centers on the measurement accuracy of fundamental constants, particularly Planck's constant, which is defined as h = 6.62607015×10-34 J⋅Hz-1 in SI units. The relationship between Planck's constant and other constants is expressed through the formula h = (α2 me c2)/(2Rc). Notably, the Rydberg constant (R) has shown significant variations in its measurements from 2010 to 2018, indicating previous inaccuracies. The discussion also touches on the Proton radius puzzle, questioning which constants are determined experimentally versus calculated.

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  • Understanding of fundamental physical constants, including Planck's constant and the Rydberg constant.
  • Familiarity with SI units and their definitions.
  • Knowledge of the fine-structure constant (α) and its significance in physics.
  • Basic grasp of experimental versus theoretical measurements in physics.
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  • Research the implications of the Proton radius puzzle on fundamental physics.
  • Explore the latest updates on the measurement of the Rydberg constant.
  • Learn about the methods used to determine Planck's constant experimentally.
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Physicists, researchers in metrology, and students studying fundamental constants and their measurements will benefit from this discussion.

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I find the values of the fundamental constants here
https://physics.nist.gov/cuu/Constants/
In anticipation of the data of 2022, I want to clarify one point.

Planck's constant is related by an exact expression to some other fundamental quantities:
$$h = \frac{\alpha^2 m_e с^2}{2R_c}\qquad (1)$$

c = 299 792 458 m⁄s (exact)
me = 9.109 383 7015(28)∙10-31 kg
α = 7.297 352 5693(11)∙10-3
Rc =3.289 841 960 2508(64)∙1015 s

The SI units are defined in such a way that, when the Planck constant is expressed in SI units, it has the exact value h = 6.62607015×10-34 J⋅Hz-1

As of 2018, R and electron spin g-factor are the most accurately measured physical constants.
https://en.wikipedia.org/wiki/Rydberg_constant

2010 R= 10 973 731.568 539 (55) m-1
2014 R=10 973 731.568 508 (65) m-1
2018 R=10 973 731.568 160 (21) m-1

We see a big leap in value.
So the previous accuracy is a bluff.
Maybe I'm wrong , but its related to the problem called Proton radius puzzle

Which value in the above formula (1) will be determined experimentally, and which one is calculated if h(exact), c(exact) ?
 
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Physics news on Phys.org
The value of Planck's constant, h, will be determined experimentally. The values of the other fundamental constants, c, me, α, and Rc, will be calculated from the exact value of h, c, and the measured values of me, α, and Rc.
 

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