A scenario for inflationary magnetogenesis without strong coupling problem

Understand

Cosmological magnetic fields pervade the entire universe, from small to large scales.

• Since they apparently extend into the intergalactic medium, it is tantalizing to believe that they have a primordial origin, possibly being produced during inflation.
• However, finding consistent scenarios for inflationary magnetogenesis is a challenging theoretical problem.
• The requirements to avoid an excessive production of electromagnetic energy, and to avoid entering a strong coupling regime characterized by large values for the electromagnetic coupling constant, typically allow one to generate only a tiny amplitude of magnetic field during inflation.