English
Related papers

Related papers: Bouncing scenario in $f(R,T)$ gravity

200 papers

The Einstein static (ES) universe has played a major role in various emergent scenarios recently proposed in order to cure the problem of initial singularity of the standard model of cosmology. In the herein model, we study the existence…

General Relativity and Quantum Cosmology · Physics 2017-01-23 Hamid Shabani , Amir Hadi Ziaie

We solve the field equations of modified gravity for $f(R)$ model in metric formalism. Further, we obtain the fixed points of the dynamical system in phase space analysis of $f(R)$ models, both with and without the effects of radiation.…

General Relativity and Quantum Cosmology · Physics 2018-01-26 Murli Manohar Verma , Bal Krishna Yadav

In this paper, we have considered flat Friedmann-Lema\^{i}tre-Robertson-Walker metric in the framework of perfect fluid models and modified $f(G)$ gravity (where $G$ is the Gauss Bonnet invariant). Particularly, we have considered…

General Relativity and Quantum Cosmology · Physics 2017-08-08 Kazuharu Bamba , M. Ilyas , M. Z. Bhatti , Z. Yousaf

Nonsingular cosmologies are investigated in the framework of f(R) gravity within the first order formalism. General conditions for bounces in isotropic and homogeneous cosmology are presented. It is shown that only a quadratic curvature…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Tomi S. Koivisto

The homogeneous and isotropic cosmological model in generalized $ f(R,T^\phi) $ theories associated with scalar field is discussed, which is motivated by the $ f(R,T) $ theory of gravity studied by Harko et al. \cite{Harko:2011kv,…

General Relativity and Quantum Cosmology · Physics 2022-12-27 J. K. Singh , Akanksha Singh , Shaily , J. Jena

We examine the evolution of universe in $f(R,T)$ gravity where $R$ is the Ricci curvature and $T$ is the trace of energy momentum tensor. We focus on the specific form $f(R,T) = R+f(T)$ and explicitly find out the relation between $f(T)$…

General Relativity and Quantum Cosmology · Physics 2016-03-16 Gang Sun , Yong-Chang Huang

Five-dimensional cosmological models with two 3-branes and with a buck cosmological constant are studied. It is found that for all the three cases ($\Lambda =0$, $\Lambda >0$, and $\Lambda <0$), the conventional space-time singularity ``big…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Hongya Liu

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 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

Locally-rotationally-symmetric Bianchi type-I viscous and non -viscous cosmological models are explored in general relativity (GR) and in f(R,T) gravity. Solutions are obtained by assuming that the expansion scalar is proportional to the…

General Relativity and Quantum Cosmology · Physics 2021-07-07 S. Jokweni , Vijay Singh , Aroonkumar Beesham

We have studied in this paper, the stability of dynamical system in $f(R)$ gravity. We have considered the $f(R)$ $\gamma$-gravity and explored its dynamical analysis. We found six critical points among which only one describes an universe…

General Relativity and Quantum Cosmology · Physics 2016-11-29 R. D. Boko , M. J. S. Houndjo , J. Tossa

We study the viability conditions for the absence of ghost, gradient and tachyonic instabilities, in scalar-torsion $f(T,\phi)$ gravity theories in the presence of a general barotropic perfect fluid. To describe the matter sector, we use…

General Relativity and Quantum Cosmology · Physics 2021-11-11 Manuel Gonzalez-Espinoza , Giovanni Otalora , Joel Saavedra

We have studied bulk viscosity in the modified $f(Q, T)$ gravity theory formalism, where $Q$ represents the non-metricity and $T$ denotes the trace of energy-momentum tensor within a flat Friedmann-Lema\^{i}tre-Robertson-Walker metric…

General Relativity and Quantum Cosmology · Physics 2021-12-01 Simran Arora , S. K. J. Pacif , Abhishek Parida , P. K. Sahoo

In this manuscript, we consider the extension of the Hilbert-Einstein action to analyze several interesting features of the theory. More specifically, the Lagrangian $f(R)$ is replaced by $f(R, L_m)$ in action, where $R$ is the Ricci…

General Relativity and Quantum Cosmology · Physics 2022-03-25 Lakhan V. Jaybhaye , Sanjay Mandal , P. K. Sahoo

We intend to study a new class of cosmological models in $f(R, T)$ modified theories of gravity, hence define the cosmological constant $\Lambda$ as a function of the trace of the stress energy-momentum-tensor $T$ and the Ricci scalar $R$,…

General Physics · Physics 2020-03-26 Safiqul Islam , Praveen Kumar , G. S. Khadekar , Tapas K Das

We investigate a bounce inflation model with a graceful exit into the Friedmann-Robertson-Walker (FRW) decelerated Universe within $f(T)$ gravity framework, where $T$ is the torsion scalar in the teleparallelism. We study the cosmic thermal…

General Relativity and Quantum Cosmology · Physics 2016-10-13 Kazuharu Bamba , G. G. L. Nashed , W. El Hanafy , Sh. K. Ibraheem

We derive an exact $f(T)$ gravity in the absence of ordinary matter in Friedmann-Robertson-Walker (FRW) universe, where $T$ is the teleparallel torsion scalar. We show that vanishing of the energy-momentum tensor $\mathcal{T}^{\mu \nu}$ of…

High Energy Physics - Theory · Physics 2016-10-19 W. El Hanafy , G. L. Nashed

In this paper, we construct an isotropic cosmological model in the $ f(Q, T) $ theory of gravity in the frame of a flat FLRW spacetime being $ Q $ the non-metricity tensor and $ T $ the trace of the energy-momentum tensor. The gravity…

General Relativity and Quantum Cosmology · Physics 2025-04-24 Akanksha Singh , Shaily , J. K. Singh , Ertan Güdekli

We investigate cosmological models with a linear inhomogeneous time-dependent equation of state for the dark energy, coupled with dark matter, leading to a bounce cosmology. Equivalent descriptions in terms of the equation-of-state…

General Relativity and Quantum Cosmology · Physics 2014-05-07 I. Brevik , V. V. Obukhov , A. V. Timoshkin

The present work deals with a FLRW cosmological model with spatial curvature and minimally coupled scalar field as the matter content. The curvature term behaves as a perfect fluid with the equation of state parameter w_K = -1/3 Using…

General Relativity and Quantum Cosmology · Physics 2024-07-09 Soumya Chakraborty , Sudip Mishra , Subenoy Chakraborty