QCD and QED corrections to light-by-light scattering

QCD and QED Corrections to Light-by-Light Scattering

We present the QCD and QED corrections to the fermion-loop contributions to light-by-light scattering, γγ → γγ, in the ultrarelativistic limit where the kinematic invariants are much larger than the masses of the charged fermions.

Two-loop corrections to Light-by-Light scattering in Supersymmetric QED∗

Abstract: We use an n-dimensional projection method to calculate helicity amplitudes for photon-photon scattering up to the two-loop level, for massless particles inside the loop. We confirm the recent standard model results found by Bern et al using another calculational method. We further apply the method to N = 1 and N = 2 supersymmetric QED. As predicted by the supersymmetric Ward identity,...

QED second order corrections on the speed of light at low temperature

We want to study thermal corrections on the speed of light at low temperature considering temperature dependence of photon vacuum polarization tensor at two-loop level in the standard QED‎. It is found that the heat bath behaves as a dispersive medium for the propagation of light and reduces its speed proportional to the second order of temperature‎. ‎Similarities and differences‎, ‎in light ...

QCD Corrections to QED Vacuum Polarization

We compute QCD corrections to QED calculations for vacuum polarization in background magnetic fields. Formally, the diagram for virtual eē loops is identical to the one for virtual qq̄ loops. However due to confinement, or to the growth of αs as p 2 decreases, a direct calculation of the diagram is not allowed. At large p we consider the virtual qq̄ diagram, in the intermediate region we discuss ...

Light-By-Light Scattering Nonlogarithmic Corrections to Hyperfine Splitting in Muonium