Related papers: Preheating in Palatini Higgs inflation
We review work on the formation of gravitino condensates via the super-Higgs effect in the early Universe. This is a scenario for both inflating the early universe and breaking local supersymmetry (supergravity), entirely independent of any…
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…
We investigated inflation in the Higgs-$R^2$ model and assumed the trajectory to follow a single-field approximation called minimal two-field mode. Using this approximation, we tried to constrain the Higgs' non-minimal coupling $\xi$.…
A new modified string-inspired modular invariant supergravity model is proposed and is applied to realize the slow roll inflation in Einstein frame, so that the model explains WMAP observations very well. Gravitino mass and their production…
Coherent oscillations of the inflaton field at the end of inflation can parametrically excite fermions in much the same way that bosons are created in preheating. Although Pauli-blocking prohibits the occupation number of created fermions…
The epochs of reheating and preheating are studied in a simple extension of the Starobinsky inflationary model, which consists of an $R^2$--correction to the Einstein--Hilbert action and an additional scalar field. We find that if the…
I present the production of matter and radiation during reheating after inflation, considering only gravitational interactions between the inflaton background and the other sectors. Processes considered are the following: i) the exchange of…
We study the post-inflationary energy transfer from the inflaton ($\phi$) into a scalar field ($\chi$) non-minimally coupled to gravity through $\xi R|\chi|^2$, considering models with inflaton potential $V_{\rm inf} \propto |\phi|^{\,p}$…
We have discussed in detail how neutrinos produced from inflaton solely through gravitational interaction can successfully reheat the universe. For this, we have introduced the well-known Type-I seesaw neutrino model. Depending on seesaw…
In this paper we investigate tensor fluctuations of the metric at the end of a Higgs inflationary period in the context of a recently introduced complex geometrical scalar-tensor theory of gravity. In our model the Higgs field has a…
We compare Higgs inflation in the metric and Palatini formulations of general relativity, with loop corrections are treated in a simple approximation. We consider Higgs inflation on the plateau, at a critical point, at a hilltop and in a…
A {\it gauge invariant} combination of LLe {\it sleptons} within the Minimal Supersymmetric Standard Model is one of the few inflaton candidates that can naturally explain population of the observable sector and creation of matter after…
Production of gravitationally coupled light moduli fields must be suppressed in the early universe, so that its decay products do not alter Big Bang Nucleosynthesis (BBN) predictions for light elements. On the other hand, the moduli quanta…
Reheating is a transition era after the end of inflation, during which the inflaton is converted into the particles that populate the Universe at later times. No direct cosmological observables are normally traceable to this period of…
We discuss gravitino production from reheating in models where the splitting between particle and sparticle masses can be larger than TeV, as naturally arising in the context of split supersymmetry. We show that such a production typically…
We study the primordial perturbations and reheating process in the models where the Gauss-Bonnet term is non-minimally coupled to the canonical and non-canonical (DBI and tachyon) scalar fields. We consider several potentials and…
In order for an inflationary universe to evolve into a hot universe, a process known as reheating is required. However, the precise mechanism of reheating remains unknown. We show that if the reheating is triggered by thermal dissipation…
We discuss two important modifications of inflationary paradigm. Until very recently we believed that inflation automatically leads to flatness of the universe, Omega = 1. We also thought that post-inflationary phase transitions in GUTs may…
We study the onset of the reheating epoch at the end of axion-driven inflation where the axion is coupled to an Abelian, $U(1)$, gauge field via a Chern-Simons interaction term. We focus primarily on $m^2\phi^2$ inflation and explore the…
Gravitino production in the primordial Universe is investigated into details. After briefly reviewing inflation, supersymmetry and supergravity, we first study the scattering of massive W bosons in the thermal bath of particles, during the…