Fine Structure Constant

Fine structure constant is a fundamental physical constant proposed by Sir Arthur Eddington in 1916. It defines the strength of electromagnetic interaction between the two elementary charged particles. It is denoted by the letter α and its also called as Sommerfeld's constant. As its a dimensionless constant, it has same numerical value in all system of units.

Sommerfeld's Constant 

Constant Name

Fine Structure Constant

Symbol : α = μ0 e^2 c / (2 h)
α = e^2 / (4 π ε0 ℏ c)

Value : 7.297 352 568(24) × 10-3

english Calculators and Converters