Related papers: Ricci Reheating on the Lattice
We extend the framework of spontaneous baryogenesis by investigating the generation of baryon asymmetry when the inflaton, $\theta$, is minimally coupled with a complex spectator scalar field $\phi$, as $\theta^2|\phi|^2$. To do so, we also…
To understand mechanisms leading to inflation and late acceleration of the Universe it is important to see how one or a set of quantum fields may evolve such that the classical energy-momentum tensor behave similar to a cosmological…
We use classical lattice simulations in 3+1 dimensions to study the interplay between the resonant production of particles during preheating and the subsequent decay of these into a set of secondary species. We choose to work in a…
We propose a new scenario for early cosmology, where inflationary de Sitter phase dynamically occurs. The effect emerges as a result of dynamics of the topologically nontrivial sectors in expanding universe. Technically the effect can be…
We reconsider the old problem of the dynamics of spontaneous symmetry breaking using 3d lattice simulations, and develop a theory of tachyonic preheating, which occurs due to the spinodal instability of the scalar field. Tachyonic…
Light massive preheat fields acquire a non-vanishing dispersion during parametric resonance from their quantum particle production. This in turn will modify the inflaton potential, which in some cases can induce a transient period of…
We revisit the reheating mechanism after the end of inflation in the non-minimal derivative coupling (NDC) to gravity with quadratic potential. This is because the inflaton of the NDC should describe the slow-roll inflation as well as the…
We investigate a class of slow roll inflationary models in the light of the recent Cosmic Microwave Background constraints from Planck 2018, ACT DR6, DESI DR1, and BICEP/\textit{Keck} 2018. The combined dataset favors a higher value of the…
Kinetic misalignment, one of the most compelling scenarios for the non-thermal generation of axion dark matter, is generally accompanied by axion fragmentation, a process in which the energy of the axion condensate is transferred to its…
We characterize the post-inflationary evolution of the equation of state of the universe from the end of inflation until the onset of radiation domination, when the inflaton is coupled to a daughter field through a trilinear interaction. We…
Understanding when inflationary perturbations become genuinely nonlinear near the horizon crossing requires methods that go beyond both linear perturbation theory and the gradient expansion. In this work, we introduce a nonlinear lattice…
We have studied preheating of field perturbations in a 3-dimensional lattice including the effect of scalar metric perturbations, in two generic models of inflation: chaotic inflation with a quartic potential, and standard hybrid inflation.…
In this work, we consider intermediate inflation in context of the Generalized Non-Minimal Derivative Coupling (GNMDC) model. In this model, inflation is driven by a canonical scalar field that is coupled not only to gravity but also to the…
If light scalar fields are present at the end of inflation, their non-equilibrium dynamics such as parametric resonance or a phase transition can produce non-Gaussian density perturbations. We show how these perturbations can be calculated…
We present a detailed and systematic analysis of the coarse-grained, nonequilibrium dynamics of a scalar inflaton field coupled to a fermion field in the latter stages of the reheating period of inflationary cosmology. We derive coupled…
We investigate the feasibility of explosive particle production via parametric resonance or tachyonic preheating in multi-field inflationary models by means of lattice simulations. We observe a strong suppression of resonances in the…
We study post-inflationary evolution in $\alpha$-attractor T-models of inflation. We consider the dynamics of both scalar fields present in these models: the inflaton and the spectator, as a negative field-space curvature may lead to…
In certain models of inflation, the postinflationary reheating of the Universe is not primarily due to perturbative decay of the inflaton field into particles, but proceeds through a tachyonic instability. In the process, long-wavelength…
In the presence of self-interactions, the post-inflationary evolution of the inflaton field is driven into the non-linear regime by the resonant growth of its fluctuations. The once spatially homogeneous coherent inflaton is converted into…
The physics of the inflationary universe requires the study of the out of equilibrium evolution of quantum fields in curved spacetime. We present the evolution for both the geometry and the matter (described by the quantum inflaton field)…