How the electron got its spin
The spectral lines of atoms are split into subtler lines under the influence of a magnetic field. UHLENBECK and GOUDSMITH in 1925 proposed to explain this by a self-rotation of the electron.
Uhlenbeck and Goudsmit treated spin as a consequence of classical rotation, while PAULI shortly afterwards emphasised that spin is a non-classical and intrinsic property.
Spin got its name from the phenomena of the deflection of the electron in a magnetic field and the splitting of spectral lines in the magnetic field.
<aside> 📌 Presumtion: Spin is an intrinsic (invariable) property of the electron. ↓3↓
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