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Related papers: Constraining $f(R)$ Gravity Models with The Late-T…

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Using techniques from singular perturbation theory, we explicitly calculate the cosmological evolution in a class of modified gravity models. By considering the (m)CDTT model, which aims to explain the current acceleration of the universe…

Astrophysics · Physics 2009-06-23 Jonathan D. Evans , Lisa M. H. Hall , Philippe Caillol

In the context of f(R, T) gravity theory for the flat Friedmann Lemaitre Robertson Walker (FLRW) model, the accelerating expansion of the universe is investigated using a specific form of the emergent Hubble parameter. Datasets from H(z),…

General Relativity and Quantum Cosmology · Physics 2025-01-16 N. Myrzakulov , S. H. Shekh , Anirudh Pradhan , Archana Dixit

In this work, a new generic parameterisation for $f(R)$ theories is presented. Our proposal for a new equation of state can reproduce an $f(R)$-like evolution that describes late and early time universe within 1-$\sigma$ C.L when we use a…

General Relativity and Quantum Cosmology · Physics 2020-11-20 N. M. Jiménez Cruz , Celia Escamilla-Rivera

We systematically review some standard issues and also the latest developments of modified gravity in cosmology, emphasizing on inflation, bouncing cosmology and late-time acceleration era. Particularly, we present the formalism of standard…

General Relativity and Quantum Cosmology · Physics 2021-05-25 S. Nojiri , S. D. Odintsov , V. K. Oikonomou

The late-time acceleration of the universe remains one of the most significant open problems in modern cosmology. Modified gravity frameworks such as $f(T)$ gravity provide a geometric alternative to dark energy by attributing cosmic…

General Relativity and Quantum Cosmology · Physics 2026-05-07 Anirudh Pradhan , S. A. Salve , V. B. Raut , S. H. Shekh

We study the late-time evolution of the Universe within the f(R,G) gravity framework, where R is the Ricci scalar and G is the Gauss-Bonnet term. To make the model tractable, we propose a parametrization scheme and determine its parameters…

General Relativity and Quantum Cosmology · Physics 2026-05-12 Santosh V. Lohakare , B. Mishra , S. K. Maurya

We investigate the cosmological implications of $f(Q)$ gravity, which is a modified theory of gravity based on non-metricity, in non-flat geometry. We perform a detailed dynamical-system analysis keeping the $f(Q)$ function completely…

General Relativity and Quantum Cosmology · Physics 2023-06-26 Hamid Shabani , Avik De , Tee-How Loo , Emmanuel N. Saridakis

In this work, we linearize the field equations of $f(R)$ gravity using the Starobinsky model, $R+R^2/(6m^2)$, and examine the modifications to General Relativity. We derive an equation for the trace, $T$, of the energy-momentum tensor,…

General Relativity and Quantum Cosmology · Physics 2026-01-28 Roger Anderson Hurtado

The review of basic cosmological properties of four-dimensional F(R)-gravity, including FRW equations of motion and its accelerating solutions, generalized fluid and scalar-tensor representation of the theory is done. Cosmological…

High Energy Physics - Theory · Physics 2015-05-19 Shin'ichi Nojiri , Sergei D. Odintsov

We study cosmological constraints on the various accelerating models of the universe using the time evolution of the cosmological redshift of distant sources. The important characteristic of this test is that it directly probes the…

General Relativity and Quantum Cosmology · Physics 2015-03-13 Deepak Jain , Sanjay Jhingan

We present a novel approach for reconstructing the $f(Q)$ gravitational theory using parameterizations of the deceleration parameter or alternative options. This method enables the development of modified gravity scenarios that align with…

General Relativity and Quantum Cosmology · Physics 2025-02-26 G. G. L. Nashed

The reconstruction scheme is developed for modified $f(R)$ gravity with realistic matter (dark matter, baryons, radiation). Two versions of such theory are constructed: the first one describes the sequence of radiation and matter…

High Energy Physics - Theory · Physics 2008-11-26 Shin'ichi Nojiri , Sergei D. Odintsov

The $f(R)$ gravity models proposed by Hu-Sawicki and Starobinsky are generic for local gravity constraints to be evaded. The large deviations from these models either result into violation of local gravity constraints or the modifications…

High Energy Physics - Theory · Physics 2010-03-26 I. Thongkool , M. Sami , R. Gannouji , S. Jhingan

We consider general curvature-invariant modifications of the Einstein-Hilbert action that become important only in regions of extremely low space-time curvature. We investigate the far future evolution of the universe in such models,…

Modified gravity models are subject to a number of consistency requirements which restrict the form that the function $F(R)$ can take. We study a particular class of $F(R)$ functions which satisfy various constraints that have been found in…

Astrophysics · Physics 2010-04-06 Stephen A. Appleby , Richard A. Battye

The new model of modified $F(R)$ gravity theory with the function $F(R) = R+(a/\gamma) \arcsin(\gamma R)$ is suggested and investigated. Constant curvature solutions corresponding to the extremum of the effective potential are obtained. We…

General Physics · Physics 2015-07-20 S. I. Kruglov

We explore the late time cosmological dynamics of the Universe within the framework of $f(Q,\mathcal{L}_{m})$ gravity by considering the specific form $f(Q, \mathcal{L}_m)=-Q+2\mathcal{L}_m+\gamma$. To describe the cosmic pressure…

General Relativity and Quantum Cosmology · Physics 2025-08-08 Amit Samaddar , S. Surendra Singh

$f(R)$ modifications of Einstein's gravity is an interesting possibility to explain the late time acceleration of the Universe. In this work we explore the cosmological viability of one such $f(R)$ modification proposed in (Kruglov:2013).…

General Relativity and Quantum Cosmology · Physics 2016-07-13 Koushik Dutta , Sukanta Panda , Avani Patel

We discuss the possibility that suitable modifications of gravity could account for some amount of the radiation we observe today, in addition to the possibility of explaining the present speed up of the universe. We start introducing and…

General Relativity and Quantum Cosmology · Physics 2015-12-02 Joao Morais , Mariam Bouhmadi-Lopez , Salvatore Capozziello

We consider f(R,T) modified theory of gravity, in which the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar and the trace of the energy-momentum tensor of the matter, in order to investigate the dark-matter…

General Relativity and Quantum Cosmology · Physics 2016-11-02 Raziyeh Zaregonbadi , Mehrdad Farhoudi , Nematollah Riazi
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