Charged particles, gauge invariance, and molecular electrodynamics

✍ Scribed by R. G. Woolley

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 225 KB
• Volume: 74
• Category: Article
• ISSN: 0020-7608
• DOI: 10.1002/(sici)1097-461x(1999)74:5<531::aid-qua9>3.0.co;2-h

✦ Synopsis

A general account of the interaction of charges with electromagnetic radiation is presented; the charges are treated in the nonrelativistic approximation for Ž . simplicity not an essential assumption . The two main approaches in the literature based Ž . on either the potentials of the electromagnetic field minimal coupling or the polarization Ž . fields of the charges e.g., the multipolar Hamiltonian are presented in a unified framework that characterizes them as simply different viewpoints of the same general structure. This structure is very suitable for a discussion of the gauge invariance of the theory. The final quantum mechanical Hamiltonian derived here has recently been shown to provide the basis for a proof of the gauge invariance of its associated S-matrix to all orders of perturbation theory, provided the S-matrix is taken on the energy shell.