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Related papers: Reconstructing inflation in scalar-torsion $f(T,\p…

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The reconstruction of an inflationary universe in the context of one $f(\phi)T$ gravity, in which $T$ corresponds to the trace of energy momentum tensor is studied. To realize this reconstruction during the inflationary epoch, we consider…

General Relativity and Quantum Cosmology · Physics 2023-10-12 Ramon Herrera , Carlos Rios

The reconstruction of an inflationary universe in the context of the Galileon model or G-model, considering as attractors the scalar spectral index $n_S(N)$ and the tensor to scalar ratio $r(N)$ as a function of the number of e-folding $N$…

General Relativity and Quantum Cosmology · Physics 2018-08-08 Ramon Herrera

Recent cosmological observations are in good agreement with the scalar spectral index $n_s$ with $n_s-1\sim -2/N$, where $N$ is the number of e-foldings. Quadratic chaotic model, Starobinsky model and Higgs inflation or $\alpha$-attractors…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-03 Takeshi Chiba

We investigate inflation in modified gravity framework by introducing a direct coupling term between a scalar field $\phi$ and the trace of the energy momentum tensor $T$ as $f(\phi,T) = 2 \phi( \kappa^{1/2} \alpha T + \kappa^{5/2} \beta…

General Relativity and Quantum Cosmology · Physics 2022-10-17 Ashmita , Payel Sarkar , Prasanta Kumar Das

If inflation is to be considered in an unbiased way, as possibly originating from one of a wide range of underlying theories, then observations need not be simply applied to reconstructing the inflaton potential, V(\phi), or a specific…

Astrophysics · Physics 2008-12-18 Rachel Bean , Daniel J. H. Chung , Ghazal Geshnizjani

We investigate the reconstruction of standard and generalized Rastall gravity inflationary models, using the scalar spectral index and the Rastall parameter expressed as functions of the number of $e-$folds $N$. Within a general formalism,…

General Relativity and Quantum Cosmology · Physics 2025-12-09 Ramon Herrera , Carlos Rios

This paper discusses a simple procedure to reconstruct f (R)-gravity models from exact cosmological solutions of the Einstein field equations with a noninteracting classical scalar field-and-radiation background. From the kind of…

General Relativity and Quantum Cosmology · Physics 2017-09-15 Heba Sami , Joseph Ntahompagaze , Amare Abebe

We reconstruct the potential of minimally coupling inflation model which produces small value of the tensor-scalar ratio. In these inflation models, tensor-scalar ratio is proportional to 1/N^2 scalar spectral index is in good agreement…

General Relativity and Quantum Cosmology · Physics 2019-04-10 Jun Chen

The reconstruction of a braneworld inflationary universe considering the parametrization (or attractor) of the scalar spectral index $n_s(N)$ in terms of the number of $e$-foldings N is developed. We also study the possibility that the…

General Relativity and Quantum Cosmology · Physics 2019-05-15 Ramon Herrera

Starting from parametrization of scalar perturbations generated during inflation in terms of $e$--fold $N$ and using an approach recently developed by Starobinsky, dubbed "direct smooth reconstruction", we show that, in the slow--roll…

General Relativity and Quantum Cosmology · Physics 2024-01-26 Gianluca Giacomozzi , Sergio Zerbini

During the inflationary epoch, we investigate the reconstruction of the background variables within the framework of Einstein-Gauss-Bonnet gravity, considering the scalar spectral index $n_s(N)$ and the tensor-to-scalar ratio $r(N)$, where…

General Relativity and Quantum Cosmology · Physics 2026-01-28 Ramón Herrera , Carlos Ríos

We study Higgs-like inflation in the framework of scalar-torsion gravity, focusing on the general class of $f(T,\phi)$ theories in which gravitation is mediated by torsion rather than curvature. Motivated by the increasing precision of…

General Relativity and Quantum Cosmology · Physics 2026-01-01 Nitesh Kumar , Giovanni Otalora , Rodrigo Reyes , Bastian Espinoza , Manuel Gonzalez-Espinoza , Emmanuel N. Saridakis

In this work, we extend the bottom-up reconstruction framework of $F(R)$ gravity to other modified gravities, and in particular for $f(\phi)R$ and mimetic $F(R)$ gravities. We investigate which are the important conditions in order for the…

General Relativity and Quantum Cosmology · Physics 2018-03-14 S. D. Odintsov , V. K. Oikonomou

The reconstruction of a warm inflationary universe model from the scalar spectral index $n_S(N)$ and the tensor to scalar ratio $r(N)$ as a function of the number of e-folds $N$ is studied. Under a general formalism we find the effective…

General Relativity and Quantum Cosmology · Physics 2018-04-18 Ramon Herrera

In this article we analyze the reconstruction of inflation in the framework of a non-canonical theory. In this sense, we study the viability of reconstructing the background variables assuming a non-lineal kinetic term given by…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-15 Ramon Herrera , Carlos Rios

We study Quadratic Inflation with the inflaton field $\phi$ coupled non-minimally to the curvature scalar $R$, so that the potential during inflation is of the form $V\propto m^2\phi^2+\xi R\phi^2$. We show that with a suitable choice of…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-13 Tommi Tenkanen

Generalized slow roll conditions and parameters are obtained for a general form of scalar-tensor theory (with no external sources), having arbitrary functions describing a nonminimal gravitational coupling F(\phi), a Kahler-like kinetic…

General Relativity and Quantum Cosmology · Physics 2009-11-07 J. R. Morris

We investigate a class of inflationary models in modified gravity theories which contain a non-minimal coupling between gravity and a scalar field $\phi$ (inflaton) as $f(R,T)=R \bigl(1+\alpha+ \kappa^4 \beta T \bigr)+\kappa^2\gamma T $…

General Relativity and Quantum Cosmology · Physics 2024-12-03 Payel Sarkar , Ashmita , Prasanta Kumar Das

In this paper, we present quantitative constraints on the scalar field potential for a general class of inflationary models. (1) We first consider the reconstruction of the inflationary potential for given primordial density fluctuation…

Astrophysics · Physics 2009-10-22 Fred C. Adams , Katherine Freese

The reconstruction of a k-essence inflationary universe, considering the unification between the swampland criteria and the attractor given by the scalar spectral index $n_S(N)$ together with the slow roll parameter $\epsilon(N)$in terms of…

General Relativity and Quantum Cosmology · Physics 2021-01-01 Ramon Herrera
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