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We present the complete solution to the classification problem regarding the variational symmetries of the generalized Brans-Dicke cosmological model in the presence of a second scalar field minimally coupled to gravity and the generalized…

General Relativity and Quantum Cosmology · Physics 2024-12-25 Andronikos Paliathanasis

The Noether symmetry approach is useful tool to restrict the arbitrariness in a gravity theory when the equations of motion are underdetermined due to the high number of functions to be determined in the ansatz. We consider two…

General Relativity and Quantum Cosmology · Physics 2016-05-11 U. Camci , A. Yildirim , I. Basaran Oz

We consider cosmological models based on the scalar-torsion gravity implying non-minimal coupling between torsion and the scalar field with certain relations between model's parameters. Based on observational constraints on the values of…

General Relativity and Quantum Cosmology · Physics 2024-11-14 I. V. Fomin , S. V. Chervon , E. S. Dentsel

In the framework of teleparallel equivalent of general relativity, we study a gravity theory where a scalar field beyond its minimal coupling, is also coupled with the vector torsion through a non-minimal derivative coupling. After a…

General Relativity and Quantum Cosmology · Physics 2016-12-14 Behnaz Fazlpour

It has been shown earlier that Noether symmetry does not admit a form of F(R) corresponding to an action in which F(R) is coupled to scalar-tensor action for gravity or even for pure F(R) gravity taking anisotropic model into account. Here,…

General Relativity and Quantum Cosmology · Physics 2013-11-12 Nayem Sk. , Abhik Kumar Sanyal

A geometric framework, called multicontact geometry, has recently been developed to study action-dependent field theories. In this work, we use this framework to analyze symmetries in action-dependent Lagrangian and Hamiltonian field…

Mathematical Physics · Physics 2025-03-06 Xavier Rivas , Narciso Román-Roy , Bartosz M. Zawora

A class of generalized Galileon cosmological models, which can be described by a point-like Lagrangian, is considered in order to utilize Noether's Theorem to determine conservation laws for the field equations. In the…

General Relativity and Quantum Cosmology · Physics 2017-03-23 N. Dimakis , Alex Giacomini , Sameerah Jamal , Genly Leon , Andronikos Paliathanasis

It is well known that the Noether symmetry approach proves to be very useful not only to fix physically viable cosmological models but also to reduce dynamics and achieve exact solutions. In this work, We examine a formal framework of…

General Relativity and Quantum Cosmology · Physics 2018-09-05 Phongpichit Channuie , Davood Momeni

The search for Noether point symmetries for non-relativistic charged particle motion is reduced to the solution for a set of two coupled, linear partial differential equations for the electromagnetic field. These equations are completely…

Classical Physics · Physics 2007-05-23 F. Haas

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 develop the $n$-dimensional cosmology for $f(\mathcal{G})$ gravity, where $\mathcal{G}$ is the \emph{Gauss-Bonnet} topological invariant. Specifically, by the so-called Noether Symmetry Approach, we select $f(\mathcal{G})\simeq…

General Relativity and Quantum Cosmology · Physics 2021-11-29 Francesco Bajardi , Salvatore Capozziello

This paper explores exact cosmological solutions of anisotropic universe model through Noether symmetry technique in energy-momentum squared gravity. This theory resolves the primordial singularity and provides viable cosmological…

General Relativity and Quantum Cosmology · Physics 2023-05-24 M. Sharif , M. Zeeshan Gul

Scalar-tensor theories are studied in the context of cosmological evolution, where the expansion history of the Universe is reconstructed. It is considered quintessence/phantom models, where inflation and cosmic acceleration are reproduced.…

High Energy Physics - Theory · Physics 2008-12-11 Diego Sáez-Gómez

The paper deals with a non--minimally coupled scalar field in the background of homogeneous but anisotropic Kantowski--Sachs space--time model. The form of the coupling function of the scalar field with gravity and the potential function of…

General Relativity and Quantum Cosmology · Physics 2018-05-23 Sourav Dutta , Muthusamy Lakshmanan , Subenoy Chakraborty

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

We explore Noether gauge symmetries of FRW and Bianchi I universe models for perfect fluid in scalar-tensor gravity with extra term $R^{-1}$ as curvature correction. Noether symmetry approach can be used to fix the form of coupling function…

General Relativity and Quantum Cosmology · Physics 2014-03-04 M. Sharif , Saira Waheed

Multiple scalar fields appear in vast modern particle physics and gravity models. When they couple to gravity non-minimally, conformal transformation is utilized to bring the theory into Einstein frame. However, the kinetic terms of scalar…

General Relativity and Quantum Cosmology · Physics 2021-09-22 Yong Tang , Yue-Liang Wu

We study the evolution of cosmological perturbations, using a hybrid approximation scheme which upgrades the weak-field limit of Einstein's field equations to account for post-Newtonian scalar and vector metric perturbations and for…

Astrophysics · Physics 2007-05-23 Carmelita Carbone , Sabino Matarrese

In any diffeomorphism invariant theory of gravity, one can define a Noether charge arising from the invariance of the Lagrangian under diffeomorphisms. We have determined the Noether charge for scalar-tensor theories of gravity, in which…

General Relativity and Quantum Cosmology · Physics 2025-02-19 Krishnakanta Bhattacharya , Sumanta Chakraborty

We show that the recent results of \ [Int. J. Mod. Phys. D 25 (2016) 1650051] on the application of Lie/Noether symmetries in scalar field cosmology are well-known in the literature while the problem could have been solved easily under a…

General Relativity and Quantum Cosmology · Physics 2017-01-25 Andronikos Paliathanasis , Spyros Basilakos , Michael Tsamparlis
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