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Related papers: Accelerating universe in modified teleparallel gra…

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We consider the evolution of cosmological gravitational waves in scalar-tensor theory and $F(R)$ gravity theory as typical models of the modified gravity. Although the propagation speed is not changed from the speed of light, the…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-04 Shin'ichi Nojiri , Sergei D. Odintsov

We consider the cosmology of a brane-world scenario in the framework of teleparallel and $f(T)$ gravity in a way that matter is localized on the brane. We show that the cosmology of such branes is different from the standard cosmology in…

General Relativity and Quantum Cosmology · Physics 2015-04-02 K. Atazadeh , A. Eghbali

In this paper, we investigate and analyze the cosmological dynamics of the universe, with an effect of modified $f(R)$ gravity emerging at cosmological scale. We choose the Einstein frame as a physical frame. We consider phase portraits of…

Astrophysics · Physics 2007-05-23 Daris Samart

A novel function for modified gravity is proposed, $f(R, T)=R+\lambda R^2+2\beta\ln(T)$, with constants $\lambda$ and $\beta$, scalar curvature $R$, and the trace of stress energy tensor $T$, satisfying $T=\rho-3p>0$. Subsequently, two…

General Physics · Physics 2020-06-16 Emilio Elizalde , Nisha Godani , Gauranga C. Samanta

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 study flat Friedmann-Lemaitre-Robertson-Walker cosmological models for a scalar field coupled nonminimally to teleparallel gravity with generic coupling and potential functions. The goal of this paper is to determine the conditions under…

General Relativity and Quantum Cosmology · Physics 2016-08-08 Laur Jarv , Alexey Toporensky

In this paper, we investigate the accelerating phase of the Universe within the context of $f(R,L_m,T)$ gravity theory, where $R$, $L_m$, and $T$ represent the Ricci scalar, matter Lagrangian, and the trace of the energy-momentum tensor,…

General Relativity and Quantum Cosmology · Physics 2025-11-19 V. A. Kshirsagar , A. S. Agrawal , S. A. Kadam , Vishwajeet S. Goswami

Although big bang cosmology effectively models even the most puzzling observational data, it offers no insight into why the cosmological expansion should occur at all. In this paper it is suggested that a finite Universe poses particular…

General Physics · Physics 2007-05-23 Alasdair Macleod

We explore an extension of the symmetric teleparallel gravity denoted the $f(Q)$ theory, by considering a function of the nonmetricity invariant $Q$ as the gravitational Lagrangian. Some interesting properties could be found in the $f(Q)$…

General Relativity and Quantum Cosmology · Physics 2019-06-24 Jianbo Lu , Xin Zhao , Guoying Chee

This work investigates the cosmology of a thick brane within the context of $f(\mathbb{Q})$ gravity, an extension of symmetric teleparallelism. Using a five-dimensional Friedmann-Lema\^itre-Robertson-Walker metric, we solve the field…

General Relativity and Quantum Cosmology · Physics 2026-03-05 J. J. Ramos , J. E. G. Silva

The evolution of universe in Brans-Dicke (BD) theory is discussed in this paper. Considering a parameterized scenario for BD scalar field $\phi=\phi_{0}a^{\alpha}$ which plays the role of gravitational "constant" $G$, we apply the Markov…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-14 Jianbo Lu , Weiping Wang , Lixin Xu , Yabo Wu

Currently, in order to explain the accelerated expansion phase of the universe, several alternative approaches have been proposed, among which the most common are dark energy models and alternative theories of gravity. Although these…

General Relativity and Quantum Cosmology · Physics 2021-08-24 I. S. Farias , P. H. R. S. Moraes

An accelerating flat universe with a variable cosmological term is obtained in the Robertson-Walker metric. The variable cosmological term is defined by the correction terms of the metric tensor field. Simple solutions of the scale factor…

Astrophysics · Physics 2015-06-24 Takao Fukui

We have explored a transitioning cosmic model, depicting late-time accelerated expansion in $f(R,T^{\phi})$ theory of gravity for an isotropic and homogeneous universe, where the trace of energy-momentum tensor $T^{\phi}$ is the function of…

General Relativity and Quantum Cosmology · Physics 2024-03-29 Bhojraj Singh Jayas , Vinod Kumar Bhardwaj

In the framework of teleparallel gravity, the Friedman-Robertson-Walker cosmological model with scalar tensor theory where scalar field is non-minimally coupled to both the torsion scalar and boundary term is studied. Utilizing the Noether…

General Relativity and Quantum Cosmology · Physics 2018-08-29 Ganim Gecim , Yusuf Kucukakca

In this paper, we study the nonlinear electrodynamics in the framework of $f(T)$ gravity for FRW universe along with dust matter, magnetic and torsion contributions. We evaluate the equation of state and deceleration parameters to explore…

General Relativity and Quantum Cosmology · Physics 2015-06-19 M. Sharif , Shamaila Rani

Starting from the generalized Raychaudhuri equation with torsion and non-metricity, and considering an FLRW spacetime we derive the most general form of acceleration equation in the presence of torsion and non-metricity. That is we derive…

General Relativity and Quantum Cosmology · Physics 2022-03-08 Damianos Iosifidis

In an attempt to look for a viable mechanism leading to a present-day accelerated expansion, we investigate the possibility that the observed cosmic speed up may be recovered in the framework of the Rastall's theory, relying on the…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-12 Monica Capone , Vincenzo Fabrizio Cardone , Matteo Luca Ruggiero

Homogeneous isotropic models with two torsion functions built in the framework of the Poincare gauge theory of gravity based on general expression of gravitational Lagrangian by certain restrictions on indefinite parameters are analyzed…

General Relativity and Quantum Cosmology · Physics 2015-03-19 A. S. Garkun , V. I. Kudin , A. V. Minkevich , Yu. G. Vasilevsky

Generic cosmological models derived from higher dimensional theories with warped extra dimensions have a nonzero cosmological constant-like term induced on the 3+1 space-time, or a physical 3-brane. In the scenario where this 3+1 space-time…

General Relativity and Quantum Cosmology · Physics 2011-01-13 Ishwaree P Neupane
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