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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

We summarize our work on "hidden" Noether symmetries of multifield cosmological models and the classification of those two-field cosmological models which admit such symmetries.

High Energy Physics - Theory · Physics 2020-04-22 Lilia Anguelova , Elena Mirela Babalic , Calin Iuliu Lazaroiu

Finding spherically symmetric exact solutions in modified gravity is usually a difficult task. In this paper we use the Noether's symmetry approach for a modified Teleparallel theory of gravity labelled as $f(T,B)$ gravity where $T$ is the…

General Relativity and Quantum Cosmology · Physics 2019-12-02 Sebastian Bahamonde , Ugur Camci

Quantum cosmology with quintom dark energy model has been investigated in the present work using symmetry analysis of the underlying physical system. In the background of the flat FLRW model quintom cosmological model has been studied using…

General Physics · Physics 2021-04-23 Sourav Dutta , Muthusamy Lakshmanan , Subenoy Chakraborty

Noether symmetries from geodetic Lagrangian for time-conformal plane symmetric spacetime are presented. Here, time conformal factor is used to find the approximate Noether symmetries. This is a generalization of the idea discussed by I.…

General Relativity and Quantum Cosmology · Physics 2015-11-04 Farhad Ali , Tooba Feroze

An alternative to the postulate of dark energy required to explain the accelerated expansion of the universe is to adopt an inhomogeneous cosmological model to explain the supernovae data without dark energy. We adopt a void cosmology…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-02 J. W. Moffat

The breaking of space-time symmetries and the non-conservation of the associated Noether charges constitutes a central artifact in lattice field theory. In prior work we have shown how to overcome this limitation for classical actions…

High Energy Physics - Lattice · Physics 2024-10-10 A. Rothkopf , W. A. Horowitz , J. Nordström

In this paper, we investigate the dynamics of the universe on the background of f-essence when a non-minimal coupling with gravity. Field equations are obtained and using the Noether theorem, explicit forms of the coupling function and the…

General Physics · Physics 2017-05-26 Tolkynay Myrzakul , Ertan Gudekli , Shynaray Myrzakul , Ratbay Myrzakulov

We present nonsingular cosmological models with a variable cosmological term described by the second-rank symmetric tensor $\Lambda_{mn}$ evolving from $\Lambda g_{mn}$ to $\lambda g_{mn}$ with $\lambda < \Lambda$. All $\Lambda_{mn}$…

General Relativity and Quantum Cosmology · Physics 2009-11-10 K. A. Bronnikov , A. Dobosz , I. G. Dymnikova

In this work, we apply the formalism of dynamical systems to analyze the viability of the $\Lambda$CDM model in a generalized form of the hybrid metric-Palatini gravity theory written in terms of its dynamically equivalent scalar-tensor…

General Relativity and Quantum Cosmology · Physics 2024-09-06 João Luís Rosa

We discuss the application of the Hojman's Symmetry Approach for the determination of conservation laws in Cosmology, which has been recently applied by various authors in different cosmological models. We show that Hojman's method for…

General Relativity and Quantum Cosmology · Physics 2016-02-04 A. Paliathanasis , P. G. L. Leach , S. Capozziello

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 determine the most general time-independent Noether symmetries of two-field cosmological models with rotationally-invariant scalar manifold metrics. In particular, we show that such models can have hidden symmetries, which arise if and…

High Energy Physics - Theory · Physics 2019-09-10 Lilia Anguelova , Elena Mirela Babalic , Calin Iuliu Lazaroiu

It is shown that isotropic cosmology in the Riemann-Cartan spacetime allows to solve the problem of cosmological singularity as well as the problems of invisible matter components - dark energy and dark matter. All cosmological models…

General Relativity and Quantum Cosmology · Physics 2011-02-04 A. V. Minkevich

The current standard model of cosmology, the LambdaCDM model, is based on the homogeneous FLRW solutions of the Einstein equations to which some perturbations are added to account for the CMB features and structure formation at large…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-14 Marie-Noëlle Célérier

We use our N\"other Symmetry Approach to study the Einstein equations minimally coupled with a scalar field, in the case of Bianchi universes of class A and B. Possible cases, when such symmetries exist, are found and two examples of exact…

General Relativity and Quantum Cosmology · Physics 2011-05-19 Salvatore Capozziello , Giuseppe Marmo , Claudio Rubano , Paolo Scudellaro

This paper is devoted to investigate $f(R)$ gravity using Noether symmetry approach. For this purpose, we consider Friedmann Robertson-Walker (FRW) universe and spherically symmetric spacetimes. The Noether symmetry generators are evaluated…

General Relativity and Quantum Cosmology · Physics 2012-08-03 M. Farasat Shamir , Adil Jhangeer , Akhlaq Ahmad Bhatti

Assuming homogeneous isotropic Lambda-CDM cosmology allows Lambda, spatial curvature and dark matter density to be inferred from large scale structure observations such as supernovae. The purpose of this paper is to extend this to allow…

General Relativity and Quantum Cosmology · Physics 2011-02-02 Toby Wiseman , Benjamin Withers

In this work we study the magnitude-redshift relation of a non-standard cosmological model. The model under consideration was firstly investigated within a special case of metric-affine gravity (MAG) and was recently recovered via different…

General Relativity and Quantum Cosmology · Physics 2009-04-03 Dirk Puetzfeld , Xuelei Chen

Lie symmetry analysis is an established method for generating symmetries of differential equations. We apply this method together the generalized fundamental theorem of double reduction. In particular, Noether symmetries and some associated…

Analysis of PDEs · Mathematics 2019-12-13 Phetogo Masemola , Thilivhali Phidane
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