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Related papers: f(R) cosmology by Noether's symmetry

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The purpose of the current article is to present a brief albeit accurate presentation of the main tools used in the study of symmetries of Lagrange equations for holonomic systems and subsequently to show how these tools are applied in the…

General Relativity and Quantum Cosmology · Physics 2018-06-18 Michael Tsamparlis , Andronikos Paliathanasis

We explore the recently introduced modified Gauss-Bonnet gravity [1], $f(\mathcal{G},T)$ pragmatic with $\mathcal{G}$, the Gauss-Bonnet term, and ${T}$, the trace of the energy-momentum tensor. Noether symmetry approach has been used to…

General Physics · Physics 2017-01-31 M. Farasat Shamir , Mushtaq Ahmad

This work aims to investigate some possible emergence of relativistic compact stellar objects in modified $f(\mathcal{G})$ gravity using Noether symmetry approach. For this purpose, we assume static spherically symmetric spacetime in the…

General Relativity and Quantum Cosmology · Physics 2020-06-08 M. Farasat Shamir , Tayyaba Naz

There is a no-go theorem forbidding flat and closed FLRW solutions in massive gravity on a flat reference metric, while open solutions are unstable. Recently it was shown that this no-go theorem can be overcome if at least some matter…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-21 Adam R. Solomon , Jonas Enander , Yashar Akrami , Tomi S. Koivisto , Frank Könnig , Edvard Mörtsell

Anisotropic cosmological models are investigated in the frame work of $f(R)$ gravity in the metric formalism. Plane symmetric models are considered to incorporate anisotropy in the expansion rates along different spatial directions. The…

General Relativity and Quantum Cosmology · Physics 2017-04-26 S K Tripathy , B Mishra

Noether symmetry of F(R) theory of gravity in vacuum or in matter dominated era yields three-half power law of R. We show that this particular curvature invariant term is very special in the context of isotropic and homogeneous cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-18 Kaushik Sarkar , Nayem Sk. , Soumendranath Ruz , Subhra Debnath , Abhik Kumar Sanyal

In this paper, we determine regular black hole solutions using a very general $f(R)$ theory, coupled to a non-linear electromagnetic field given by a Lagrangian $\mathcal{L}_{NED}$. The functions $f(R)$ and $\mathcal{L}_{NED}$ are left in…

General Relativity and Quantum Cosmology · Physics 2016-05-25 Manuel E. Rodrigues , Julio C. Fabris , Ednaldo L. B. Junior , Glauber T. Marques

In this work we study the spherical symmetric solutions of $f(R)$ gravity in the metric formalism. We show that for a generic $f(R)$ gravity, the spherical symmetric solution is consistent with the modified gravity equations except in the…

Astrophysics · Physics 2015-05-13 Reza Saffari , Sohrab Rahvar

New type of nonsingular oscillating solutions for the Universe described by cosmological equations of gauge theories of gravity is presented. Advantages of these solutions with respect to existing nonsingular solutions within framework of…

Astrophysics · Physics 2007-05-23 G. Vereshchagin

In this paper, we use the Hojman symmetry approach to find new $(2+1)$-dimensional $f(R)$ gravity solutions, in comparison to Noether symmetry approach. In the special case of Hojman symmetry vector $X=R$, we recover $(2+1)$-dimensional BTZ…

General Relativity and Quantum Cosmology · Physics 2022-03-29 F. Darabi , M. Golmohammadi , A. Rezaei-Aghdam

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 work, exact solutions of static and spherically symmetric space-times are analyzed in f(R) modified theories of gravity coupled to nonlinear electrodynamics. Firstly, we restrict the metric fields to one degree of freedom,…

General Relativity and Quantum Cosmology · Physics 2012-06-22 Lukas Hollenstein , Francisco S. N. Lobo

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

The present work explores different evolutionary phases of isotropically homogeneous and flat cosmos filled with dust fluid in non-minimally coupled gravity. We consider different models of this gravity to discuss the presence of symmetry…

General Relativity and Quantum Cosmology · Physics 2024-07-04 Iqra Nawazish , M. Sharif

In the framework of scalar-tensor gravity, we consider non-flat interacting quintessence cosmology where a scalar field is interacting with dark matter. Such a scalar field can be a standard or a phantom one. We use the Noether Symmetry…

General Relativity and Quantum Cosmology · Physics 2023-07-06 Ester Piedipalumbo , Stefano Vignolo , Pasquale Feola , Salvatore Capozziello

In the background of homogeneous and isotropic flat FLRW space-time, both classical and quantum cosmology has been studied for teleparallel dark energy (DE) model. Using Noether symmetry analysis, not only the symmetry vector but also the…

General Relativity and Quantum Cosmology · Physics 2024-07-12 Dipankar Laya , Roshni Bhaumik , Sourav Dutta , Subenoy Chakraborty

The problem of matching different regions of spacetime in order to construct inhomogeneous cosmological models is investigated in the context of Lagrangian theories of gravity constructed from general analytic functions f(R), and from…

General Relativity and Quantum Cosmology · Physics 2013-04-24 Timothy Clifton , Peter Dunsby , Rituparno Goswami , Anne Marie Nzioki

In this paper, we study anisotropic universe using Noether symmetries in modified gravity. In particular, we choose locally rotationally symmetric Bianchi type-$I$ universe for the analysis in $f(R,\mathcal{G})$ gravity, where $R$ is the…

General Relativity and Quantum Cosmology · Physics 2017-05-18 M. Farasat Shamir , Fiza Kanwal

So far, the standard attitude to solve the Friedmann equations in the simultaneous presence of radiation $R$, matter $M$ and cosmological constant ${\Lambda}$ is to find solutions $R_R (t)$, $R_M (t)$ and $R_{\Lambda} (t)$ separately for…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-03 Giorgio Galanti , Marco Roncadelli

We discuss the most general field equations for cosmological spacetimes for theories of gravity based on non-linear extensions of the non-metricity scalar and the torsion scalar. Our approach is based on a systematic symmetry-reduction of…

General Relativity and Quantum Cosmology · Physics 2022-01-05 Fabio D'Ambrosio , Lavinia Heisenberg , Simon Kuhn
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