Vacuum Polarization


vacuum polarization

[′vak·yəm ‚pō·lə·rə′zā·shən] (quantum mechanics) A process in which an electromagnetic field gives rise to virtual electron-positron pairs that effectively alter the distribution of charges and currents that generated the original electromagnetic field.

Polarization, Vacuum

 

in the quantum theory of fields, the change in the distribution of charged virtual particle-antipar-ticle pairs under the influence of an electromagnetic field. The vacuum polarization predicted by quantum electrodynamics produces effects that can be detected experimentally. These include shifts in the potential energy of the electrons in an atom, corrections to the cross section for elastic scattering at large angles, and the scattering of light by light—as yet unobserved in a Coulomb field.