Palatini approach and large-scale magnetogenesis

  title={Palatini approach and large-scale magnetogenesis},
  author={Massimo Giovannini},
  journal={Journal of Cosmology and Astroparticle Physics},
  • M. Giovannini
  • Published 6 October 2021
  • Physics
  • Journal of Cosmology and Astroparticle Physics
Large-scale magnetogenesis is analyzed within the Palatini approach when the gravitational action is supplemented by a contribution that is nonlinear in the Einstein-Hilbert term. While the addition of the nonlinear terms does not affect the scalar modes of the geometry during the inflationary phase, the tensor-to-scalar ratio is nonetheless suppressed. In this context it is plausible to have a stiff phase following the standard inflationary stage provided the potential has a quintessential… 
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