Thermal photon dispersion law and modified black‐body spectra

Based on the postulate that photon propagation is governed by an SU(2) gauge principle we numerically compute the one‐loop dispersion for thermalized photon propagation on the radiatively induced mass shell. Formerly, the dispersion was addressed by assuming p² = 0. While this approximation turns out to be excellent for temperatures ≤ 2 T_CMB the exact result exhibits a much faster (power‐like) shrinking of the gap in the black‐body spectral intensity with rising temperature. Our previous statements on anomalous large‐angle CMB temperature‐temperature correlations, obtained in the approximation p² = 0, remain valid.