fine structure constant, α

https://dx.doi.org/10.1351/goldbook.F02389
Atomic fundamental physical constant, α = μ 0 e 2 c 0 2 h = 7.297 353 08 33 × 10 −3, where μ 0 is the permeability of vacuum, e the elementary charge, h the Planck constant, and c 0 the speed of light.
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