Magnetogenesis in bouncing cosmology

Understand

We consider the process of magnetogenesis in the context of nonsingular bounce cosmology.

• We show that large primordial magnetic fields can be generated during contraction without encountering strong coupling and backreaction issues.
• The fields may seed large-scale magnetic fields with observationally interesting strengths.
• This result leads to a theoretical constraint on the relation of the energy scale of the bounce cosmology to the number of effective e-folding of the contracting phase in the case of scale invariance for the power spectrum of primordial magnetic fields.