Maxwell-Kostelecký electromagnetism and cosmic magnetization

The Lorentz violating term in the photon sector of Standard Model Extension, LK=−14(kF)αβμνFαβFμν (here referred to as the Kostelecký term), breaks conformal invariance of electromagnetism and enables a superadiabatic amplification of magnetic vacuum fluctuations during inflation. For a wide range of values of parameters defining Lorentz symmetry violation and inflation, the present-day magnetic field can have an intensity of order of nanogauss on megaparsec scales and then could explain the large-scale magnetization of the universe.