The transverse part of the three-point Green function of massless QED is determined to the lowest order in position space. Taken together with the evaluation of the longitudinal part in arXiv:0803.2630, this gives a relation for QED which is analogous to the star-triangle relation. We relate our result to conformal-invariant three-point functions.

Accurate calculations of the binding energies, the hyperfine splitting , the bound-electron g-factor, and the parity nonconservation effects in heavy few-electron ions are considered. The calculations include the relativistic, quantum electrodynamic (QED), electron-correlation, and nuclear effects. The theoretical results are compared with available experimental data. A special attention is foc...

We examine the propagation of light in the presence of various modifications of the QED vacuum in the limit of low frequency. A polarization summed and direction averaged-light cone condition is derived from the equation of motion which arises from the effective QED action. Several applications are given concerning vacuum modifications caused by, e.g., strong fields, Casimir systems and finite ...

Recently, we have developed a unified approach to QED in arbitrary linearly responding media in equilibrium—media that give rise to absorption [Phys. Rev. A 75, (2007) 053813]. In the present paper we show that, under appropriate conditions, the theory can be quite naturally generalized to amplifying media the effect of which is described within the framework of linear response theory. We discu...

We compute the leading-log QED, the next-to-leading-log QED-QCD, and the electroweak corrections to the charm quark contribution relevant for the rare decay K+ → π+νν̄. The corresponding parameter Pc(X) is increased by up to 2% with respect to the pure QCD estimate to Pc(X) = 0.372 ± 0.015 for mc(mc) = (1.286±0.013)GeV, αs(MZ) = 0.1176±0.0020 and |Vus| = 0.2255. For the branching ratio we find B...

Abstract: The classic argument by Polyakov showing that monopoles produce confinement in the Higgs phase of the Georgi-Glashow model is generalized to study the spectrum of k-strings. We find that the leading-order low-density approximation yields Casimir scaling in the weakly-coupled 3-d SU(N) Georgi-Glashow model. Corrections to the Casimir formula are considered. When k ∼ N , the non-diluten...

where e, m and g are the charge, mass and gyromagnetic factor of the particle. In the Dirac theory of a charged pointlike spin-1/2 particle, g = 2, and QED effects slightly increase the g value. Conventionally, a quantity a ≡ (g−2)/2 is referred to as the anomalous magnetic moment. The electron and muon anomalous magnetic moments have been measured with a very high relative accuracy of 0.24 ppb...

Investigations of the hyperfine splitting and the g factor in highly charged ions give an access to a test of boundstate QED in strongest electromagnetic fields available at present for experimental study. To date, accurate measurements of the ground-state hyperfine structure and of the g factor were performed in H-like ions. An extention of such kind of experiments to highly charged Li-like io...