相关论文: Generation of helical magnetic fields from inflati…
We study the generation of helical magnetic fields during single field inflation induced by an axial coupling of the electromagnetic field to the inflaton. During slow roll inflation, we find that such a coupling always leads to a blue…
We describe a simple scenario of inflationary magnetogenesis based on a helical coupling to electromagnetism. It allows to generate helical magnetic fields of strength of order up to $10^{- 7}\,\text{G}$, when extrapolated to the current…
We study the generation of helical magnetic fields during inflation by considering a model which does not suffer from strong coupling or large back-reaction. Electromagnetic conformal invariance is broken only during inflation by coupling…
There has been a growing evidence for the existence of magnetic fields in the extra-galactic regions, while the attempt to associate their origin with the inflationary epoch alone has been found extremely challenging. We therefore take into…
We consider a scale-invariant helical magnetic field generated during inflation. We show that, if the mean magnetic helicity density of such a field is measured, it can be used to determine a lower bound on the duration of inflation. Upper…
We study the generation of helical magnetic fields in a model of inflationary magnetogenesis which is free from the strong coupling and back-reaction problems. To generate helical magnetic fields, we add an $f^2 \tilde{F}^{\mu\nu}…
Primordial magnetic field generated in the inflationary era can act as a viable source for the present day intergalactic magnetic field of sufficient strength. We present a fundamental origin for such a primordial generation of the magnetic…
We study the inflationary generation of helical magnetic fields from the Riemann coupling with the electromagnetic field. Most models in the literature introduce non-minimal coupling to the electromagnetic fields with a scalar field, hence,…
We revisit the mechanism of helical magnetogenesis during inflation with a parity violating interaction using the formalism of stochastic inflation. One of the polarization of the gauge field undergoes tachyonic growth leading to the…
We propose a novel scenario to generate primordial magnetic fields during inflation induced by an oscillating coupling of the electromagnetic field to the inflaton. This resonant mechanism has two key advantages over previous proposals.…
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 field is generically and naturally broken.…
We consider the possibility of inflationary magnetogenesis due to dynamical couplings of the electromagnetic fields to gravity. We find that large primordial magnetic fields can be generated during inflation without the strong coupling…
In this work we compute the production of magnetic fields in models of axion inflation coupled to the hypercharge sector of the Standard Model through a Chern-Simons interaction term. We make the simplest choice of a quadratic inflationary…
We consider helical coupling to electromagnetism and present a simple scenario of evolution of the coupling function leading to a viable inflationary magnetogenesis without the problem of back-reaction. In this scenario, helical magnetic…
If the conformal invariance of electromagnetism is broken during inflation, then primordial magnetic fields may be produced. If this symmetry breaking is generated by the coupling between electromagnetism and a scalar field---e.g. the…
The generation of a magnetic field in the Early Universe is considered, due to the gravitational production of the Z-boson field during inflation. Scaled to the epoch of galaxy formation this magnetic field suffices to trigger the galactic…
The hot plasma above the electroweak scale contains (hyper) charged scalar particles which are coupled to Abelian gauge fields. Scalars may interact with gravity in a non-conformally invariant way and thus their fluctuations can be…
The generation of primordial magnetic seed fields during inflation is studied in a theory derived from the one-loop vacuum polarization effective action of the photon in a curved background. This includes terms which couple the curvature to…
We investigate the generation of large scale magnetic fields in the universe from quantum fluctuations produced in the inflationary stage. By coupling these quantum fluctuations to the dilaton field and Ricci scalar, we show that the…
We study the generation of magnetic fields during inflation making use of a coupling of the inflaton and moduli fields to electromagnetism via the photon kinetic term, and assuming that the coupling is an increasing function of time. We…