On the variation of the gauge couplings during inflation

  title={On the variation of the gauge couplings during inflation},
  author={Massimo Giovannini},
  journal={Physical Review D},
It is shown that the evolution of the (Abelian) gauge coupling during an inflationary phase of de Sitter type drives the growth of the two-point function of the magnetic inhomogeneities. After examining the constraints on the variation of the gauge coupling arising in a standard model of inflationary and post-inflationary evolution, magnetohydrodynamical equations are generalized to the case of time evolving gauge coupling. It is argued that large scale magnetic fields can be copiously… Expand
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