# Effective horizons, junction conditions and large-scale magnetism

@article{Giovannini2017EffectiveHJ,
title={Effective horizons, junction conditions and large-scale magnetism},
author={Massimo Giovannini},
journal={The European Physical Journal C},
year={2017},
volume={77},
pages={1-7}
}
• M. Giovannini
• Published 29 June 2017
• Physics
• The European Physical Journal C
The quantum mechanical generation of hypermagnetic and hyperlectric fields in four-dimensional conformally flat background geometries rests on the simultaneous continuity of the effective horizon and of the extrinsic curvature across the inflationary boundary. The junction conditions for the gauge fields are derived in general terms and corroborated by explicit examples with particular attention to the limit of a sudden (but nonetheless continuous) transition of the effective horizon. After…
1 Citations
Primordial magnetic fields from gravitationally coupled electrodynamics in nonsingular bounce cosmology
• Physics
Science China Physics, Mechanics & Astronomy
• 2018
We in this paper study a class of mechanism of the production of the primordial magnetic field (PMF) in the non-singular bouncing cosmology, through the coupling of the electromagnetic field to

## References

SHOWING 1-10 OF 52 REFERENCES
Inflationary magnetogenesis, derivative couplings, and relativistic Van der Waals interactions
When the gauge fields have derivative couplings to scalars, like in the case of the relativistic theory of Van der Waals (or Casimir-Polder) interactions, conformal invariance is broken but the
Spectator Higgs field, large-scale gauge fields, and the nonminimal coupling to gravity
Even if the Higgs field does not affect the evolution of the background geometry, its massive inhomogeneities induce large-scale gauge fields whose energy density depends on the slow-roll parameters,
Symmetries of inflationary magnetogenesis and the plasma initial conditions
As soon as the geometry expands quasi-exponentially the plasma sources are customarily tuned to zero as if the duration of the inflationary phase was immaterial for the gauge field fluctuations at
Electric-magnetic duality and the conditions of inflationary magnetogenesis
The magnetogenesis scenarios triggered by the early variation of the gauge coupling are critically analyzed. In the absence of sources, it is shown that the electric power spectra can be explicitly
Generation of large scale magnetic fields in single-field inflation
• Physics
• 2007
We consider the generation of large scale magnetic fields in slow-roll inflation. The inflaton field is described in a supergravity framework where the conformal invariance of the electromagnetic
Hypermagnetic gyrotropy, inflation and the baryon asymmetry of the Universe
We investigate the production of the hypermagnetic gyrotropy when the electric and magnetic gauge couplings evolve at different rates, as it happens in the relativistic theory of the van der Waals
Large-scale magnetic fields in the inflationary universe
• Physics, Mathematics
• 2007
The generation of large-scale magnetic fields is studied in the inflationary cosmology. We consider a very general situation in which the conformal invariance of the Maxwell field is violated through
A scenario for inflationary magnetogenesis without strong coupling problem
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
Adiabatic Modes in Cosmology
We show that the field equations for cosmological perturbations in the Newtonian gauge always have an adiabatic solution, for which a quantity $\mathcal{R}$ is nonzero and constant in all eras in the