Electron spin
Espín del electrón
- Date
- 1925 · confidence high
- Place
- University of Leiden, Netherlands
- Credited to
- George Uhlenbeck; Samuel Goudsmit; Ralph Kronig
- People
- 👤 George Eugene Uhlenbeck1900–1988👤 Samuel Goudsmit1902–1978
- Field
- Cosmos & Earth
⚠️ Disputed: the sources disagree.
What was discovered
The electron has an intrinsic angular momentum of value h/4π and an associated magnetic moment, which explains the anomalous Zeeman effect and fine structure. It is a purely quantum property with no classical analogue.
Kronig proposed the idea months earlier and abandoned it after Pauli's criticism; Uhlenbeck and Goudsmit published it with Ehrenfest's support.
What it led to
- Dirac equation (spin as a relativistic consequence)
- Nuclear and electron spin resonance
- Spintronics
- Classification of particles by spin (bosons and fermions)
Built on
Made possible
- Magnetic resonance imaging (MRI)1973-1977
- Giant magnetoresistance hard disks
- Spin qubits