Effective horizons, junction conditions and large-scale magnetism
arXiv:1706.09824 · doi:10.1140/epjc/s10052-017-5105-1
Abstract
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 reducing the dynamics to a pair of integral equations related by duality transformations, we compute the power spectra and deduce a novel class of logarithmic corrections which turn out to be, however, numerically insignificant and overwhelmed by the conductivity effects once the gauge modes reenter the effective horizon. In this perspective the magnetogenesis requirements and the role of the postinflationary conductivity are clarified and reappraised. As long as the total duration of the inflationary phase is nearly minimal, quasi-flat hypermagnetic power spectra are comparatively more common than in the case of vacuum initial data.
12 pages, 1 figure
References in corpus (9)
- Generation of Large-Scale Magnetic Fields in Single-Field Inflation
- Large-scale magnetic fields in the inflationary universe
- Higgs Dynamics during Inflation
- A scenario for inflationary magnetogenesis without strong coupling problem
- The interrelation between the generation of large-scale electric fields and that of large-scale magnetic fields during inflation
- Property of the spectrum of large-scale magnetic fields from inflation
- Generation of large-scale magnetic fields, non-Gaussianity, and primordial gravitational waves in inflationary cosmology
- Magnetogenesis in bouncing cosmology
- Inflationary dynamics of kinetically-coupled gauge fields