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Related papers: Inflation in $f(R,T)$ Gravity

200 papers

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

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 study inflation in the framework of $f(T)$-gravity in the presence of a canonical scalar field. After reviewing the basic equations governing the background cosmology in $f(T)$-gravity, we turn to study the cosmological perturbations and…

General Relativity and Quantum Cosmology · Physics 2016-02-02 K. Rezazadeh , A. Abdolmaleki , K. Karami

Inflation in the framework of $f(R)$ modified gravity is revisited. We study the conditions that $f(R)$ should satisfy in order to lead to a viable inflationary model in the original form and in the Einstein frame. Based on these criteria…

High Energy Physics - Theory · Physics 2018-10-17 M. Amin , S. Khalil , M. Salah

In this paper, I consider a $f(R, G, T)$ modified gravity model where $R$ represents the Ricci scalar, $G$ denotes the Gauss-Bonnet invariant, and $T$ signifies the trace of the stress-energy tensor. This model is coupled with two distinct…

General Relativity and Quantum Cosmology · Physics 2024-09-04 Farzad Milani

In this work we investigate a inflationary scenario generated by a large scalar field $\phi$ that non-minimally couples to a $f(R)$ modified gravity model. For a Starobinsky's like model, it is found that along a particular flat direction,…

High Energy Physics - Phenomenology · Physics 2017-01-17 Romy H. S. Budhi

We examine an inflationary model in $R + R^2$ gravity with torsion, where $R^2$ denotes five independent quadratic curvature invariants; it turns out that only two free parameters remain in this model. We show that the behavior of the scale…

General Relativity and Quantum Cosmology · Physics 2009-02-12 Chih-Hung Wang , Yu-Huei Wu

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

In this paper, we explore the equivalence between two theories, namely f(R) and scalar-tensor theories of gravity. We use this equivalence to explore several f(R) toy models focusing on the inflation epoch of the early universe. The study…

General Relativity and Quantum Cosmology · Physics 2018-11-21 Joseph Ntahompagaze , Jean Damascene Mbarubukeye , Shambel Sahlu , Amare Abebe

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 work, we study the inflationary cosmology in modified gravity theory $f(R, T) = R + 2 \lambda T$ ($\lambda$ is the modified gravity parameter) with three distinct class of inflation potentials (i) $\phi^p e^{-\alpha\phi}$, (ii)…

General Relativity and Quantum Cosmology · Physics 2023-01-09 Ashmita , Payel Sarkar , Prasanta Kumar Das

In this work we study a modified version of $f(R)$ gravity in which higher order kinetic terms of a scalar field are added in the action of vacuum $f(R)$ gravity. This type of theory is a type of $k$-essence $f(R)$ gravity, and it belongs…

General Relativity and Quantum Cosmology · Physics 2019-03-27 S. Nojiri , S. D. Odintsov , V. K. Oikonomou

We shall investigate the inflation for the D-brane model, motivated by the modified gravity $F(\phi,T)$. This gravity has been recently introduced in the literature. The feasibility of the D-brane inflation theory in the $F(\phi,T)$-gravity…

General Relativity and Quantum Cosmology · Physics 2025-08-04 Feyzollah Younesizadeh , Davoud Kamani

We explore conformal-anomaly driven inflation in $F(R)$ gravity without invoking the scalar-tensor representation. We derive the stress-energy tensor of the quantum anomaly in the flat homogeneous and isotropic universe. We investigate a…

High Energy Physics - Theory · Physics 2014-08-13 Kazuharu Bamba , R. Myrzakulov , S. D. Odintsov , L. Sebastiani

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

We investigate slow roll inflation and the creation of primordial density fluctuations in the framework of $f(Q,T)$ gravity. Our focus is on constraining the evolution of both the background and perturbations in this theory, specifically…

General Relativity and Quantum Cosmology · Physics 2026-02-09 Parviz Goodarzi

In the general framework of Metric-Affine theories of gravity, where the metric and the connection are independent variables, we consider actions quadratic in the Ricci scalar curvature and the Holst invariant (the contraction of the…

General Relativity and Quantum Cosmology · Physics 2023-03-21 Ioannis D. Gialamas , Kyriakos Tamvakis

In this paper we investigate the inflationary dynamics of an $f(R)$ gravity in the presence of a canonical scalar field. We specifically choose the cosmological evolution to be a quasi-de Sitter evolution and also the $f(R)$ gravity is…

General Relativity and Quantum Cosmology · Physics 2018-08-01 K. Kleidis , V. K. Oikonomou

We examine a scalar-tensor model of gravity that is globally scale-invariant. When adapted to a spatially flat Robertson-Walker metric, the equations of motion describe a dynamical system that flows from an unstable de Sitter space to a…

General Relativity and Quantum Cosmology · Physics 2023-06-27 Massimiliano Rinaldi , Chiara Cecchini , Anish Ghoshal , Debangshu Mukherjee

We propose the study of constant-roll inflation in $F(R)$ gravity. We use two different approaches, one that relates an $F(R)$ gravity to well known scalar models of constant-roll and a second that examines directly the constant-roll…

General Relativity and Quantum Cosmology · Physics 2017-12-06 S. Nojiri , S. D. Odintsov , V. K. Oikonomou