Abundances of light nuclei formed during primordial nucleosynthesis are predicted by Standard Big Bang Model (SBBM). Here, we evaluate the second-order quantum electro dynamics (QED) corrections to the change in these parameters during primordial nucleosynthesis due to modifications to mass and coupling using finite temperature effects. These are the contributions from the dynamically generated masses for electrons and photons in the finite temperature background. Relative variations in neutron decay rate, total energy density of the universe, relative change in neutrino temperature etc. with two-loops corrections to electron mass, at the timescale when QED corrections were relevant, have been estimated.
Radiative Corrections to Muon and Neutron Decay