English
Related papers

Related papers: On Inflation and Axionic Dark Matter in a Scaled G…

200 papers

In this paper, we investigate models where a scalar field driving inflation is minimally coupled with gravity and it is subjected to a scalar potential. We present several examples of coupling between the field and gravity, and we furnish…

General Relativity and Quantum Cosmology · Physics 2016-03-01 Shynaray Myrzakul , Ratbay Myrzakulov , Lorenzo Sebastiani

We study the cosmological inflation within the context of f(Q, T) gravity, wherein Q is the nonmetricity scalar and T is the trace of the matter energy-momentum tensor. By choosing a linear combination of Q and T, we first analyze the…

General Relativity and Quantum Cosmology · Physics 2022-08-30 Maryam Shiravand , Saeed Fakhry , Mehrdad Farhoudi

In this work we construct a formalism that can reveal the general characteristics of classes of viable $F(R)$ inflationary theories. The assumptions we make is that the slow-roll era occurs, and that the de Sitter scalaron mass $m^2(R)$ of…

General Relativity and Quantum Cosmology · Physics 2025-09-30 V. K. Oikonomou

We review modified $F(R)$ gravity as realistic candidate to describe the observable universe expansion history. We show that recent cosmic acceleration, radiation/matter-dominated epoch and inflation could be realized in the framework of…

High Energy Physics - Theory · Physics 2008-07-08 Shin'ichi Nojiri , Sergei D. Odintsov

We investigate warm intermediate scenario of the cosmological inflation in $F(T)$ gravity in the limit of high dissipation. The inflationary expansion is driven by the scalar inflaton while the gravitational dynamics follow from the $F(T)$…

General Relativity and Quantum Cosmology · Physics 2015-06-09 Mubasher Jamil , Davood Momeni , Ratbay Myrzakulov

The logarithmic $R^2$-corrected $F(R)$ gravity is investigated as a prototype model of modified gravity theories with quantum corrections. By using the auxiliary field method, the model is described by the general relativity with a scalaron…

General Relativity and Quantum Cosmology · Physics 2019-10-23 T. Inagaki , Y. Matsuo , H. Sakamoto

In this paper, we worked in the framework of an inflationary $f(R,T)$ theory, in the presence of a canonical scalar field. More specifically, the $f(R,T)=\gamma R+2\kappa\alpha T$ gravity. The values of the dimensionless parameters $\alpha$…

General Relativity and Quantum Cosmology · Physics 2023-08-01 V. K. Oikonomou , Konstantinos-Rafail Revis , Ilias C. Papadimitriou , Maria-Myrto Pegioudi

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…

General Relativity and Quantum Cosmology · Physics 2025-07-28 Feyzollah Younesizadeh , Davoud Kamani

We investigate the cosmic inflation scenario of a specific $f(R)$ model that contains more than one higher-order term in $R$. The $f(R)$ considered here has the terms $R^2$, $R^3$, and $R^4$ along with the linear term. A rigorous…

General Relativity and Quantum Cosmology · Physics 2022-11-16 Sahazada Aziz , Sohan Kumar Jha , Anisur Rahaman

By applying a particular kind of modified gravity, we study the inflation. Precisely, we extend our investigations beyond the Einstein's gravity to explore the Natural inflation model via the term $F(\phi)T$. We compute the inflation…

General Relativity and Quantum Cosmology · Physics 2025-07-30 Feyzollah Younesizadeh , Davoud Kamani

We review recent trends on inflationary dynamics in the context of viable modified gravity theories. After providing a general overview of the inflationary paradigm emphasizing on what problems of hot Big Bang theory inflation solves, and a…

General Relativity and Quantum Cosmology · Physics 2023-09-20 S. D. Odintsov , V. K. Oikonomou , I. Giannakoudi , F. P. Fronimos , E. C. Lymperiadou

The article presents modeling of inflationary scenarios for the first time in the $f(R,T)$ theory of gravity. We assume the $f(R,T)$ functional from to be $R + \eta T$, where $R$ denotes the Ricci scalar, $T$ the trace of the…

General Relativity and Quantum Cosmology · Physics 2020-08-03 Snehasish Bhattacharjee , J. R. L. Santos , P. H. R. S. Moraes , P. K. Sahoo

We study early universe with a particular form of F(T) Telleparallel gravity theory, in which inflation is driven by a scalar field. To ensure slow rollover, two different potentials are chosen in a manner, such that they remain almost flat…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-20 Manas Chakrabortty , Nayem Sk , Susmita Sanyal , Abhik Kumar Sanyal

In this paper, we employ the Palatini formalism to investigate the dynamics of large-field inflation using a renormalizable polynomial inflaton potential in the context of $f(R,\phi)$ gravity. Assuming instant reheating, we make a…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-20 Nilay Bostan , Canan Karahan , Ozan Sargın

A class of viable $F(R)$ gravity models which can provide a unified description of inflation with the dark energy era is confronted with the latest observational data on the dark energy era. These models have the unique characteristic that…

General Relativity and Quantum Cosmology · Physics 2025-09-23 S. D. Odintsov , V. K. Oikonomou , G. S. Sharov

We study symmetry-breaking inflation within the framework of metric-affine gravity. By introducing a non-minimal coupling, $\beta(\phi)\tilde{\cal R}$, between the Holst invariant and the inflaton, both small-field and large-field…

General Relativity and Quantum Cosmology · Physics 2025-05-28 Ioannis D. Gialamas , Antonio Racioppi

Affine gravity, a gravity theory based on affine connection with no notion of metric, supports scalar field dynamics only if scalar fields have non-vanishing potential. The non-vanishing vacuum energy ensures that the cosmological constant…

General Relativity and Quantum Cosmology · Physics 2018-03-19 Hemza Azri , Durmus Demir

In this work we shall study a class of $f(R,\phi)$ gravity models which during the inflationary era, which is the large curvature regime, result to an effective inflationary Lagrangian that contains a rescaled Einstein-Hilbert term $\alpha…

General Relativity and Quantum Cosmology · Physics 2022-03-14 V. K. Oikonomou , Ifigeneia Giannakoudi , Achilles Gitsis , Konstantinos-Rafail Revis

In this paper we shall consider an exponential inflationary model in the context of vacuum $F(R)$ gravity. By using well-known reconstruction techniques, we shall investigate which $F(R)$ gravity can realize the exponential inflation…

General Relativity and Quantum Cosmology · Physics 2018-03-14 V. K. Oikonomou

This study examines how inflationary dynamics are affected by $f(R)$ theories with a non-minimal coupling between matter and curvature. Both positive and negative corrections to the minimal coupling of General Relativity are considered, and…

General Relativity and Quantum Cosmology · Physics 2026-01-29 Miguel Barroso Varela , Orfeu Bertolami , Andreas Mantziris