Related papers: Hilltop Supernatural Inflation
Future research studies of cosmic microwave background polarization seems likely to provide a more improved upper bound of $r \le 0.03$ on the tensor-to-scalar ratio(r). In our work, we have done the reheating study of mutated hilltop…
We consider the stimulated emission of gravitons from an initial state of thermal equilibrium, under the action of the cosmic gravitational background field. We find that the low-energy graviton spectrum is enhanced if compared with…
We use Instant Preheating as a mechanism to reheat the universe when its evolution is modeled by a non-oscillating background. Once we obtain the reheating temperature, we calculate the number of e-folds using two different methods, which…
We derive analytic bounds on the shape of the primordial power spectrum in the context of single-field inflation. In particular, the steepest possible growth has a spectral index of $n_s - 1 = 4$ once transients have died down. Its primary…
In cosmic inflation driven by a scalar gauge singlet field with a tree level Higgs potential, the scalar to tensor ratio r is estimated to be larger than 0.036, provided the scalar spectral index n_s >= 0.96. We discuss quantum smearing of…
In many models of inflation, reheating is realized through a coupling between the inflaton and the Higgs boson. Often, the mass of the inflaton is of order $10^{13}~$GeV determined by the amplitude of the scalar fluctuation spectrum.…
By using a No-Scale Supergravity model, which was proved well to explain WMAP observations appropriately, a mechanism of preheating just after the end of inflation is investigated. By using the canonically normalized and diagonalized…
The minimal supersymmetric (or F-term) hybrid inflation is defined by a unique renormalizable superpotential, fixed by a $U(1)$ R-symmetry, and it employs a canonical K\"{a}hler potential. The inflationary potential takes into account both…
We have realized non-minimal Higgs inflation and standard hybrid inflation in the supersymmetric flipped $SU(5)$ model with $U(1)_R$ symmetry using the no-scale form of the K\"{a}hler potential. In non-minimal Higgs inflation the waterfall…
Despite its importance for modeling the homogeneous hot early universe very little is experimentally known about the magnitude of the reheating temperature, leaving an uncertainty of remarkable 18 orders of magnitude. In this paper we…
Measuring the primordial power spectrum on small scales is a powerful tool in inflation model building, yet constraints from Cosmic Microwave Background measurements alone are insufficient to place bounds stringent enough to be appreciably…
Minimal supersymmetric hybrid inflation based on a minimal Kahler potential predicts a spectral index n_s\gsim 0.98. On the other hand, WMAP three year data prefers a central value n_s \approx 0.95. We propose a class of supersymmetric…
We eliminate the parameters originally present in models of inflation of the $\alpha$-attractor type in favor of the scalar spectral index $n_s$ and the tensor-to-scalar ratio $r$. We then write expressions for the number of $e$-folds…
Assuming that inflation is succeeded by a phase of matter domination, which corresponds to a low temperature of reheating $T_r<10^9\rm{GeV}$, we evaluate the spectra of gravitational waves induced in the post-inflationary universe. We work…
We re-examine the constraints on the density perturbation spectrum, including its spectral index $n$, from the production of primordial black holes. The standard cosmology, where the Universe is radiation dominated from the end of inflation…
The Atacama Cosmology Telescope (ACT) collaboration has reported a scalar spectral index $ n_s~=~0.9743~\pm~0.0034 $. This is substantially larger than the classical prediction of non-minimally coupled inflation models such as Higgs…
In many moduli stabilization schemes in string theory, the scale of inflation appears to be of the same order as the scale of supersymmetry breaking. For low-scale supersymmetry breaking, therefore, the scale of inflation should also be…
The concept of early Universe inflation resolves several problems of hot Big Bang theory and quantitatively explains the origin of the inhomogeneities in the present Universe. However, it is not possible to arrange inflation in a scalar…
We have tested some simple quintessential inflation models, imposing that they match with the recent observational data provided by the BICEP and Planck's team and leading to a reheating temperature, which is obtained via gravitational…
We show that a supersymmetric renormalizable theory based on gauge group SO(10) and Higgs system {\bf {10 $\oplus$ 210 $\oplus$ 126 $\oplus$ $\overline{\bf 126}$}} with no scale supergravity can lead to a Starobinsky kind of potential for…