The seed magnetic field generated during recombination

  title={The seed magnetic field generated during recombination},
  author={Elisabetta Fenu and Cyril Pitrou and Roy Maartens},
  journal={Monthly Notices of the Royal Astronomical Society},
Non-linear dynamics creates vortical currents when the tight-coupling approximation between photons and baryons breaks down around the time of recombination. This generates a magnetic field at second order in cosmological perturbations, whose power spectrum is fixed by standard physics, without the need for any ad hoc assumptions. We present the fully general relativistic calculation of the magnetic power spectrum, including the effects of metric perturbations, second-order velocity and photon… Expand

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