Interacting Fields, Quantum Electrodynamics

Julian Schwinger, J. C. Polkinghorne

Jacques Moret‐Bailly, J -L Monnot

The stochastic electrodynamics (SED) or neoclassical electrodynamics (NED) explains a lot of optical experiments from the hypothesis that a stochastic electromagnetic field exists, equivalent to the half quantum per mode of quantum electrodynamics; we show that, in a semi-classical theory, this field must be introduced for coherence; we propose a non-linear classical model of the interaction between an atom and an electromagnetic field, to build a semi-classical theory.

Gerd Leuchs, Markus Sondermann

We review recent experimental advances in the field of efficient coupling of single atoms and light in free space. Furthermore, a comparison of efficient free space coupling and strong coupling in cavity quantum electrodynamics (QED) is given. Free space coupling does not allow for observing oscillatory exchange between the light field and the atom which is the characteristic feature of strong coupling in cavity QED. Like cavity QED, free space QED does, however, offer full switching of the light field, a 180° phase shift conditional on the presence of a single atom as well as 100% absorption probability of a single photon by a single atom. Furthermore, free space cavity QED comprises the interaction with a continuum of modes.

Benliang Li, Daniel William Hewak, Qi Jie Wang

In this article, we start our discussion on the Aharonov-Bohm effect then raise a plausible interpretation within the quantum electrodynamics (QED) framework. We provide a quantum treatment of the source of the electromagnetic potential and argue that the underlying mechanism in AB effect can be viewed as interactions between electrons described by QED theory where the interactions are mediated by virtue photons. On further analysis, we claim that the framework of one particle quantum mechanics (OPQM) can be shown, in general, as a mathematically approximated model which can be reformulated from QED theory. In addition, the classical Maxwell equations are derived from QED scattering process while both classical electromagnetic fields and potentials serve as mathematical tools that are constructed to approximate the interactions among elementary particles described by QED physics, i.e. neither classical fields nor potentials represent any real entities of nature. At the conclusion of this article, we make a few remarks on the hypnosis of the existence of magnetic monopoles.

Gunnar Källén