Related papers: Thermalized Axion Inflation
A field kinetic coupling with the Einstein tensor leads to a gravitationally enhanced friction during inflation, by which even steep potentials with theoretically natural model parameters can drive cosmic acceleration. In the presence of…
Non-abelian gauge field inflation is studied in the context of warm inflation scenario. We introduce this scenario as a mechanism that gives an end for gauge-flation model. Slow-roll parameters and perturbation parameters are presented for…
We discuss the additional perturbation introduced during inflation by quantum stress tensor fluctuations of a conformally invariant field such as the photon. We consider both a kinematical model, which deals only with the expansion…
We study the scalar-tensor-tensor non-Gaussian signal in an inflationary model comprising also an axion coupled with SU(2) gauge fields. In this set-up, metric fluctuations are sourced by the gauge fields already at the linear level…
The theory of reheating of the Universe after inflation is developed. The transition from inflation to the hot Universe turns out to be strongly model-dependent and typically consists of several stages. Immediately after inflation the field…
Inflaton couplings during warm inflation result in the production of a thermal bath. Thermal friction and fluctuations can dominate the standard de Sitter analogues, resulting in a modified slow-roll scenario with a new source of density…
In this note, we will introduce an action for warm inflation model with direct coupling between the pseudoscalar field and mass-less $SU(2)$ gauge fields. The potential of inflaton is protected against the thermal corrections in a thermal…
In this work, we investigated several inflationary scenarios within the framework of modified $f(Q,\phi)$ gravity with a nonminimal coupling between the scalar field and the nonmetricity scalar. We focused on the impact of the coupling…
$SU(2)$ gauge fields can generate large gravitational waves during inflation, if they are coupled to an axion which can be either the inflaton or a spectator field. The shape of the produced tensor power spectrum $\mathcal{P}_h$ depends on…
In models of natural inflation, the inflaton is an axion-like particle. Unfortunately, axion potentials in UV-complete theories appear to be too steep to drive inflation. We show that, even for a steep potential, natural inflation can occur…
In this work, we investigate the preheating mechanism in a disformally-coupled inflationary model where the scalar field $\phi$ (which is the inflaton field) naturally coupled to another matter field $\chi$ induced by the disformal…
The axionic inflaton with the Chern-Simons coupling may generate U(1) gauge fields and charged particles simultaneously. In order to incorporate the backreaction from the charged particles on the gauge fields, we develop a procedure to…
We show, within the single-field inflationary paradigm, that a linear non-minimal interaction $\xi\,M_P\,\phi\,R$ between the inflaton field $\phi$ and the Ricci scalar $R$ can result in successful inflation that concludes with an efficient…
The original axion natural inflation model predicts a tensor-to-scalar ratio exceeding experimental limits. Conversely, in aligned axion inflation, inflation can proceed along trajectories emerging from near a saddle point of the two-field…
In this work, we propose a model of warm inflation driven by axion-like particles interacting with $U(1)$ gauge fields, with implications for the early universe's thermal evolution. By extending traditional warm inflation models, we…
We consider a scenario in which the inflaton $\phi$ is a pseudoscalar field non-minimally coupled to gravity through a term of the form ${\cal X} R \phi^2$. The pseudoscalar is also coupled to a $U(1)$ gauge field (or an ensemble of ${\cal…
For the models of inflation driven by the potential energy of an inflaton field $\phi$, the covariant Galileon Lagrangian $(\partial\phi)^2\Box \phi$ generally works to slow down the evolution of the field. On the other hand, if the…
We use a lattice simulation to study a model of axion inflation where the inflaton is coupled to a U(1) gauge field through Chern-Simons interaction. These kinds of models have already been studied with a lattice simulation in the context…
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…
Axion inflation, i.e. an axion-like inflaton coupled to an Abelian gauge field through a Chern-Simons interaction, comes with a rich and testable phenomenology. This is particularly true in the strong backreaction regime, where the gauge…