Electrical Conduction in the Early Universe

The electrical conductivity has been calculated 1 in the early universe at temperatures below as well as above the electroweak vacuum scale, Tc ≃ 100GeV. Debye and dynamical screening of electric and magnetic interactions leads to a finite conductivity, σel ∼ T/α ln(1/α), at temperatures well below Tc. At temperatures above, W charge-exchange processes – analogous to color exchange through gluons in QCD – effectively stop left-handed charged leptons. However, right-handed leptons can carry current, resulting in σel/T being only a factor ∼ cos 4 θW smaller than at temperatures below Tc.