真空極化

真空極化張量

$\alpha_\text{eff}(p^2) = \frac{\alpha}{1 - [\Pi_2(p^2) - \Pi_2(0)]}$

參考資料

1. ^ Levine, I.; TOPAZ Collaboration. Measurement of the Electromagnetic Coupling at Large Momentum Transfer. Physical Review Letters. 1997, 78: 424–427. Bibcode:1997PhRvL..78..424L. doi:10.1103/PhysRevLett.78.424.

延伸閱讀

• For a derivation of the vacuum polarization in QED, see section 7.5 of M.E. Peskin and D.V. Schroeder, An Introduction to Quantum Field Theory, Addison-Wesley, 1995.