MathLiveFine-structure constant
The fine-structure constant gives the dimensionless strength of the electromagnetic interaction between elementary charged particles, computed from the elementary charge, the reduced Planck constant, the speed of light and the vacuum permittivity. It appears throughout atomic and particle physics, for example in the splitting of spectral lines.
\alpha = \frac{1}{4 \pi \varepsilon_0} \frac{e^2}{\hbar c}What the symbols mean
| fine-structure constant, dimensionless (approximately 1/137) | |
| vacuum permittivity (F/m) | |
| elementary charge (C) | |
| reduced Planck constant (J·s) | |
| speed of light in vacuum (m/s) |
About this formula
- FieldPhysics
- TopicAtomic and particle physics constants
- LevelUniversity
- Also calledSommerfeld's constant, Sommerfeld fine structure constant, alpha in terms of elementary charge, electromagnetic coupling constant formula, alpha equals e squared over hbar c, fine structure constant formula SI
- SourceWikidata Q5997
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