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Related papers: f(R) scalar-tensor cosmology by Noether symmetry

200 papers

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

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

We study in which conditions the Hyperextended Scalar Tensor theory in an FLRW background admits a Noether symmetry and derive the vectors field generating it.

General Relativity and Quantum Cosmology · Physics 2009-11-10 Stephane Fay

We employ a three fluid model in order to construct a cosmological model in the Friedmann Robertson Walker flat spacetime, which contains three types of matter dark energy, dark matter and a perfect fluid with a linear equation of state.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Michael Tsamparlis , Andronikos Paliathanasis

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

We perform a detailed study of the modified gravity $f(R)$ models in the light of the basic geometrical symmetries, namely Lie and Noether point symmetries, which serve to illustrate the phenomenological viability of the modified gravity…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 A. Paliathanasis , M. Tsamparlis , S. Basilakos

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

We demonstrate the existence of static, spherically symmetric globally regular, i.e. solitonic solutions of a shift-symmetric scalar-tensor gravity model with negative cosmological constant. The norm of the Noether current associated to the…

General Relativity and Quantum Cosmology · Physics 2018-08-01 Yves Brihaye , Betti Hartmann , Jon Urrestilla

Scalar field cosmology is a model for dark energy and inflation. It has been recently found that the standard Friedmann formulation of the scalar field cosmology can be expressed in a non-linear Schr\"{o}dinger-type equation. The new…

General Relativity and Quantum Cosmology · Physics 2009-06-09 Burin Gumjudpai

As it is well known, symmetry plays a crucial role in the theoretical physics. On other hand, the Noether symmetry is a useful procedure to select models motivated at a fundamental level, and to discover the exact solution to the given…

General Physics · Physics 2018-01-16 Ali Aghamohammadi

We discuss the relationship between the Noether point symmetries of the geodesic Lagrangian, in a (pseudo)Riemannian manifold, with the elements of the Homothetic algebra of the space. We observe that the classification problem of the…

General Relativity and Quantum Cosmology · Physics 2015-11-25 A. Paliathanasis , K. Krishnakumar , P. G. L. Leach

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

Cosmological models of a scalar field with dynamical equations containing fractional derivatives or derived from the Einstein-Hilbert action of fractional order, are constructed. A number of exact solutions to those equations of fractional…

General Relativity and Quantum Cosmology · Physics 2011-08-22 V. K. Shchigolev

We show that the simplest FLRW cosmological system consisting in the homogeneous and isotropic massless Einstein-Scalar system enjoys a hidden conformal symmetry under the 1D conformal group $SL(2,\mathbb{R})$ acting as Mobius…

General Relativity and Quantum Cosmology · Physics 2025-02-06 Jibril Ben Achour , Etera R. Livine

We extend the concept of quintessence to a flat nonminimally coupled scalar - tensor theories of gravity. By means of Noether's symmetries for the cosmological pointlike Lagrangian L, it is possible to exhibit exact solutions for a class of…

High Energy Physics - Theory · Physics 2009-09-25 R. de Ritis , A. A. Marino , C. Rubano , P. Scudellaro

We find exact solutions for f (T) teleparallel gravity for the cases of spherically and cylindrically symmetric tetrads. The adopted method is based on the search for Noether symmetries of point-like Lagrangians defined in Jordan and…

General Relativity and Quantum Cosmology · Physics 2020-03-18 Ali Nur Nurbaki , Salvatore Capozziello , Cemsinan Deliduman

The standard $\Lambda$CDM model of cosmology is formulated as a simple modified gravity coupled to a single scalar field ("darkon") possessing a non-trivial hidden nonlinear Noether symmetry. The main ingredient in the construction is the…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-12 David Benisty , Eduardo I. Guendelman , Emil Nissimov , Svetlana Pacheva

Spherical symmetry in $f(R)$ gravity is discussed in details considering also the relations with the weak field limit. Exact solutions are obtained for constant Ricci curvature scalar and for Ricci scalar depending on the radial coordinate.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 S. Capozziello , A. Stabile , A. Troisi

We study FRW cosmology for a double scalar - tensor theory of gravity where two scalar fields are nonminimally coupled to the geometry. In a framework to study stability and attractor solutions of the model in the phase space, we constraint…

General Physics · Physics 2015-06-03 H. Farajollahi , A. Shahabi , A. Salehi

In this paper, we consider a gravitational theory including a Dirac field that is non-minimal coupled to gravity in $2+1$ dimensions. Noether gauge symmetry approach can be used to fix the form of coupling function $F(\Psi)$ and the…

General Relativity and Quantum Cosmology · Physics 2015-02-18 Ganim Gecim , Yusuf Kucukakca , Yusuf Sucu