Related papers: A polynomial f(R) inflation model
In this work, we explored warm inflation in the background of $f(R,T)$ gravity in the strong dissipation regime. Considering scalar field for FLRW universe, we derived modified field equations. We then deduced slow-roll parameters under…
The $R^2$ inflation which is an extension of general relativity (GR) by quadratic scalar curvature introduces a quasi-de Sitter expansion of the early Universe governed by Ricci scalar being an eigenmode of d'Alembertian operator. In this…
We investigate the inflation for the quartic hilltop model via a certain type of modified gravity. Precisely, we analyze the $F(\phi) T$ term in the Einstein's gravity to examine the quartic hilltop inflation model. $T$ is the trace of the…
We discuss a five dimensional inflationary scenario based on a supersymmetric SO(10) model compactified on $S^1/(Z_2\times Z_2')$. Inflation is implemented through scalar potentials on four dimensional branes, and a brane-localized…
We study a class of models in which the inflaton is minimally coupled to gravity with a term $f(R)\vp^2$. We focus in particular on the case when $f\sim R^2$, the expansion of the scale factor is driven by the usual potential energy, while…
In this paper, we investigate chaotic inflation from scalar field subjected to potential in the framework of $f(R^2, P, Q)$-gravity, where we add a correction to Einstein's gravity based on a function of the square of the Ricci scalar…
We consider a supersymmetric hybrid inflation scenario in which the U(1) $R$-symmetry is explicitly broken by Planck scale suppressed operators in the superpotential. We provide an example with minimal K\"ahler potential, with the…
Transforming canonical scalars to the Einstein frame can give a multi-field generalization of pole inflation (namely, a scalar with a divergent kinetic term) at vanishing field-dependent Planck mass. However, to obtain an attractor, the…
The value of the tensor-to-scalar ratio $r$ in the region allowed by the latest $Planck$ 2015 measurements can be associated to a large variety of inflationary models. We discuss here the potential of future Cosmic Microwave Background…
We introduce super exponential inflation ($\omega < -1$) from a 5D Riemann-flat canonical metric on which we make a dynamical foliation. The resulting metric describes a super accelerated expansion for the early universe well-known as super…
This short note emphasises a potential tension between string models of inflation based on systems of branes and antibranes and the spectrum of strings in curved space, in particular the requirement that the leading Regge trajectory extends…
We study the effects of the Gauss-Bonnet term on the energy spectrum of inflationary gravitational waves. The models of inflation are classified into two types based on their predictions for the tensor power spectrum: red-tilted ($n_T<0$)…
We consider the polynomial inflation with the tensor-to-scalar ratio as large as possible which can be consistent with the Quantum Gravity (QG) corrections and Effective Field Theory (EFT). To get a minimal field excursion $\Delta\phi$ for…
The existence of the inflationary era in the early Universe seems to be strongly supported by recent CMB observations. However, only a few realistic inflation scenarios which have close relation to particle physics seem to have been known…
We discuss the existence of inflationary solutions in a class of renormalization group improved polynomial f(R) theories, which have been studied recently in the context of the asymptotic safety scenario for quantum gravity. These theories…
Calculating the primordial bispectrum predicted by a model of inflation and comparing it to what we see in the sky is very computationally intensive, necessitating layers of approximations and limiting the models which can be constrained.…
We study the tensor spectral index $n_t$ and the tensor-to-scalar ratio $r$ in the simplest multifield extension to single-field, slow-roll inflation models. We show that multifield models with potentials $V \sim \sum_i \lambda_i…
I investigate multi-field inflationary models with fields that decay during inflation, leading to staggered inflation. This feature is natural in many models motivated by string theory, for instance if inflatons are related to interbrane…
We investigate the inflationary universe in a theory where two scalar fields non-minimally coupling to the scalar curvature and an extra $R^2$ term exist and the conformal invariance is broken. In particular, the slow-roll inflation is…
In a previous paper I showed that a classical scalar potential with $V''/V \sim 1$ can be sufficiently flattened by quantum corrections to give rise to slow-roll inflation. In this paper I give a hybrid inflation implementation of that idea…