Lamb Shift Calculator
Calculate quantum electrodynamic (QED) Lamb shift corrections
Lamb Shift for n=2, l=0 (Hydrogen)
Lamb Shift
1057.845 MHz
= 4.375331 micro-eV
Famous 2S_{1/2} - 2P_{1/2} Splitting
1057.845 MHz
(Measured by Lamb and Retherford, 1947)
Fine Structure Scale
0.1471 meV
Lamb Shift / Fine Structure Ratio
2.9743%
Physical Origin
The Lamb shift arises from quantum electrodynamic effects:
- Vacuum polarization (virtual electron-positron pairs)
- Electron self-energy (interaction with virtual photons)
- Vertex corrections
S-states (l=0) have larger shifts because the electron has non-zero probability at the nucleus.
Key Results
Hydrogen 2S_{1/2} - 2P_{1/2}: 1057.845 MHz
Order of magnitude: alpha^5 * m_e * c^2 / hbar
The Lamb shift proved that 2S_{1/2} and 2P_{1/2} are NOT degenerate