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Related papers: Cosmology in modified $f(R,T)$-gravity

200 papers

The trace-free version of the Einstein Gravitational equations, essentially equivalent to unimodular gravity, can solve the troubling issue of the huge discrepancy between quantum field theory estimates of the vacuum energy density and the…

General Relativity and Quantum Cosmology · Physics 2014-12-31 George F R Ellis

We consider the cosmological implications of a four-dimensional extension of the Gauss-Bonnet $f(G)$ gravity, where $G$ is the Gauss-Bonnet topological invariant, in which the Einstein-Hilbert action is replaced by an arbitrary function…

General Relativity and Quantum Cosmology · Physics 2025-06-23 Ratul Mandal , Himanshu Chaudhary , Tiberiu Harko , Ujjal Debnath , G. Mustafa

In light of the statistical performance of cosmological observations, in this work we present the cosmography in $f(T,B)$ gravity. In this scenario we found a cosmological viable standard case that allows to reduce the degeneracy between…

General Relativity and Quantum Cosmology · Physics 2021-11-17 Celia Escamilla-Rivera , Geovanny A. Rave-Franco , Jackson Levi Said

We investigate cosmological solutions for the modified gravity theory obtained from quantum relative entropy between the metric of spacetime and the metric induced by the geometry and matter fields. The vacuum equations admit inflationary…

General Relativity and Quantum Cosmology · Physics 2025-12-23 Udaykrishna Thattarampilly , Yunlong Zheng

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

In recent years, modifications to General Relativity (GR) have been explored to address cosmological observations, particularly in the context of late-time cosmic acceleration. Among these, modifications based on the Teleparallel Equivalent…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-29 Saurabh Verma , Archana Dixit , Anirudh Pradhan , M. S. Barak

We study the evolution of the cosmological parameters, namely, the deceleration parameter $q(z)$ and the parameter of effective equation of state in a universe contains, besides the ordinary matter and dark energy, a self-interacting…

General Relativity and Quantum Cosmology · Physics 2015-11-04 E. H. Baffou , M. J. S. Houndjo , M. E. Rodrigues , A. V. Kpadonou , J. Tossa

Modified gravity is one of the most favorable candidates for explaining the current accelerating expansion of the Universe. In this regard, we study the viability of an alternative gravitational theory, namely $f(R,G)$, by imposing energy…

General Relativity and Quantum Cosmology · Physics 2014-01-30 K. Atazadeh , F. Darabi

We reconcile seemingly conflicting statements in the literature about the behavior of cosmological solutions in modified theories of gravity where the Einstein-Hilbert Lagrangian for gravity is modified by the addition of a function of the…

Astrophysics · Physics 2008-11-26 Ignacy Sawicki , Wayne Hu

One of the greatest problems of standard cosmology is the Big Bang singularity. Previously it has been shown that non-local ghostfree higher-derivative modifications of Einstein gravity in the ultra-violet regime can admit non-singular…

High Energy Physics - Theory · Physics 2010-12-03 Tirthabir Biswas , Tomi Koivisto , Anupam Mazumdar

We have investigated an isotropic and homogeneous cosmological model of the universe in $f(R, T^{\phi})$ gravity, where $T^{\phi}$ is the trace of the energy-momentum tensor and $R$ is the Ricci scalar. We developed and presented exact…

General Relativity and Quantum Cosmology · Physics 2023-08-10 Vinod Kumar Bhardwaj , Priyanka Garg

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 study, we explore the dynamics of the universe using a modified gravity model represented by $f(R, G, T)$, where $R$ is the Ricci scalar, $G$ is the Gauss-Bonnet invariant, and $T$ is the trace of the stress-energy tensor. The model…

General Relativity and Quantum Cosmology · Physics 2025-03-27 Farzad Milani

In this paper, we consider a theory of gravity with a metric-dependent torsion namely the $F(R,T)$ gravity, where $R$ is the curvature scalar and $T$ is the torsion scalar. We study a geometric root of such theory. In particular we give the…

General Relativity and Quantum Cosmology · Physics 2012-11-20 Ratbay Myrzakulov

In this letter, we investigate cosmology within the framework of modified $f(Q, L_m)$ gravity using the non-linear model $f(Q, L_m) = -Q + \alpha L_m^n + \beta$, where $\alpha$, $\beta$, and $n$ are free parameters. The modified Friedmann…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-02 Y. Myrzakulov , Alnadhief H. A. Alfedeel , M. Koussour , S. Muminov , E. I. Hassan , J. Rayimbaev

We consider f(R,T) modified theories of gravity, where the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar R and of the trace of the stress-energy tensor T. We obtain the gravitational field equations in the…

General Relativity and Quantum Cosmology · Physics 2011-07-14 Tiberiu Harko , Francisco S. N. Lobo , Shin'ichi Nojiri , Sergei D. Odintsov

We search for viable f(R) theories of gravity, making use of the equivalence between such theories and scalar-tensor gravity. We find that models can be made consistent with solar system constraints either by giving the scalar a high mass…

Astrophysics · Physics 2008-11-26 Thomas Faulkner , Max Tegmark , Emory F. Bunn , Yi Mao

The inflationary scenario is not the only paradigm of early universe cosmology which is consistent with current observations. General criteria will be presented which any successful early universe model must satisfy. Various ways, including…

High Energy Physics - Theory · Physics 2018-09-14 Robert H. Brandenberger

In this work, we investigate the possibility of generating an inflationary mechanism within the framework of a metric-$f(R)$ modified gravity theory, formulated in the Jordan frame. We explore whether the scalar field, non-minimally coupled…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-21 Elisa Fazzari , Chiara De Leo , Giovanni Montani , Matteo Martinelli , Alessandro Melchiorri , Guadalupe Cañas-Herrera

We show that it is possible to obtain inflation and also solve the cosmological constant problem. The theory is invariant under changes of the Lagrangian density $L$ to $L+const$. Then the constant part of a scalar field potential $V$…

General Relativity and Quantum Cosmology · Physics 2009-10-30 E. I. Guendelman , A. B. Kaganovich