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We propose a new exponential f(R) gravity model with f(R)=(R-\lambda c)e^{\lambda(c/R)^n} and n>3, \lambda\geq 1, c>0 to explain late-time acceleration of the universe. At the high curvature region, the model behaves like the \LambdaCDM…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Qiang Xu , Bin Chen

The exponential $f(R)$ gravity model provides a theoretically well-motivated extension of General Relativity, introducing a modified gravitational dynamics at late times consistent with a dynamical dark energy scenario, while recovering the…

General Relativity and Quantum Cosmology · Physics 2025-11-11 Simone D'Onofrio , Sergei Odintsov , Tiziano Schiavone

We have probed a cosmological model in $f(R)$-gravity, which is a cubic equation in scalar curvature $R$. The terms arise due to nonlinear $f(R)$ function are treated as energy due to curvature inspired geometry. As a result, we find…

General Relativity and Quantum Cosmology · Physics 2023-05-03 G. K. Goswami , Rita Rani , Harshna Balhara , J. K. Singh

A type of exponential correction to General Relativity gives viable modified gravity model of dark energy. The model behaves as $R-2\Lambda$ at large curvature where an effective cosmological constant appears, but it becomes zero in flat…

General Relativity and Quantum Cosmology · Physics 2022-01-13 L. N. Granda

We address the cosmological role of an additional ${\cal O}(1)$ eV sterile neutrino in modified gravity models. We confront the present cosmological data with predictions of the FLRW cosmological model based on a variant of $f(R)$ modified…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 A. S. Chudaykin , D. S. Gorbunov , A. A. Starobinsky , R. A. Burenin

In this article, we study the expanding nature of universe in the contest of $f(R,L_m)$ gravity theory, here $ R $ represents the Ricci scalar and $ L_m $ is the matter Lagrangian density. With a specific form of $ f(R,L_m) $, we obtain the…

General Relativity and Quantum Cosmology · Physics 2023-06-28 J. K. Singh , Shaily , Ratbay Myrzakulov , Harshna Balhara

We investigate some FLRW cosmological models in the context of Metric-Affine $F(R,Q)$ gravity, as proposed in [arXiv:1205.52666]. Here, $R$ and $Q$ are the curvature and nonmetricity scalars using non-special connections, respectively. We…

General Relativity and Quantum Cosmology · Physics 2024-08-16 Dinesh Chandra Maurya , K. Yesmakhanova , R. Myrzakulov , G. Nugmanova

Several authors have argued that self-consistent $f(R)$ gravity models distinct from $\Lambda $CDM are almost ruled out. Confronting such claims, we present a particular two-parameter $f(R)$ model that: (a) is cosmologically viable and…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-18 V Miranda , Sergio E. Joras , Ioav Waga , Miguel Quartin

We investigate a f(R) modification of gravity that is exponential in the Ricci scalar R to explain cosmic acceleration. The steepness of this dependence provides extra freedom to satisfy solar system and other curvature regime constraints.…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-07 Eric V. Linder

We investigate a spatially flat FLRW cosmological model in the framework of modified gravity described by the function \( f(R, L_m) = \alpha R + L_m^\beta + \gamma \), where \( L_m \) is the matter Lagrangian density. The modified Friedmann…

General Relativity and Quantum Cosmology · Physics 2026-02-05 G. K. Goswami , Anirudh Pradhan , Syamala Krishnannair

Considering a well-motivated $f(R)$ modified-gravity model, in which an exponential function of the curvature is included, in this paper we implement a statistical data analysis to set constraints on the parameters of the model, taking into…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-01 Mario A. Acero , A. Oliveros

In this study, we propose a reparameterization of a specific viable $f(R)$ gravity model to represent it as a perturbation of the $\Lambda$CDM model. The $f(R)$ gravity model under consideration includes two parameters, $b$ and $n$, which…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-18 A. Oliveros

In this letter, we investigate the cosmic expansion scenario of the universe in the framework of $f(R,L_m)$ gravity theory. We consider a non-linear $f(R,L_m)$ model, specifically, $f(R,L_m)=\frac{R}{2}+L_m^n + \beta$, where $n$ and $\beta$…

General Relativity and Quantum Cosmology · Physics 2023-11-02 Lakhan V. Jaybhaye , Raja Solanki , Sanjay Mandal , P. K. Sahoo

We propose a new model of cosmology based on an anisotropic background and a specific $f(R)$ theory of gravity. It is shown that field equations of $f(R)$ gravity in a Bianchi type I background give rise to a modified Friedmann equation.…

General Relativity and Quantum Cosmology · Physics 2024-03-21 Cemsinan Deliduman , Oguzhan Kasikci , Vildan Keles Tugyanoglu

For higher-derivative f(R) gravity where R is the Ricci scalar, a class of models is proposed which produce viable cosmology different from the LambdaCDM one at recent times and satisfy cosmological, Solar system and laboratory tests. These…

Astrophysics · Physics 2009-07-09 Alexei A. Starobinsky

We provide an $F(R)$ gravity description of a $\Lambda$CDM bouncing model, without the need for matter fluids or for cosmological constant. As we explicitly demonstrate, the two cosmological eras that constitute the $\Lambda$CDM bouncing…

General Relativity and Quantum Cosmology · Physics 2015-06-23 S. D. Odintsov , V. K. Oikonomou

New corrections to General Relativity are considered in the context of modified $f(R)$ gravity, that satisfy cosmological and local gravity constraints. The proposed models behave asymptotically as $R-2\Lambda$ at large curvature and show…

General Relativity and Quantum Cosmology · Physics 2022-01-13 L. N. Granda

A modified f(R) gravity model has been recently proposed in Phys. Rev. Lett. 102, 221101 (2009) [arXiv:0905.1941] whose cosmological behaviour is clearly distinguishable from LCDM. Contrary to previous opinions which consider that…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-29 A. de la Cruz-Dombriz , A. Dobado , A. L. Maroto

In this investigation, we perform an observational statistical analysis in the theory of $ f(R, L_m) $ gravity. The proposed theoretical model is based on the Ricci scalar's non-linear contribution. We use a distinct parameterization for…

General Relativity and Quantum Cosmology · Physics 2024-08-30 J. K. Singh , Shaily , Akanksha Singh , Harshna Balhara , Joao R. L. Santos

This paper delves into the late-time accelerated expansion of the universe and the evolution of cosmic structures within the context of a specific \( f(R, L_m) \) gravity model, formulated as \( f(R, L_m) = \lambda R + \beta L_m^\alpha +…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-05 Shambel Sahlu , Alnadhief H. A. Alfedeel , Amare Abebe
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