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Related papers: Noether Symmetries in $f(T,T_G)$ Cosmology

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Noether symmetry for higher order gravity theory has been explored, with the introduction of an auxiliary variable which gives the only correct quantum desccription of the theory, as shown in a series of earlier papers. The application of…

Astrophysics · Physics 2008-11-26 A. K. Sanyal , B. Modak , C. Rubano , E. Piedipalumbo

Gauge symmetries in teleparallel gravity, together with the identities among the dynamical equations they provide, are analyzed in relation to the way they condition the coupling between matter and gravity. Particularly, the coupling of…

General Relativity and Quantum Cosmology · Physics 2023-01-02 Rafael Ferraro

We propose an extension of the symmetric teleparallel gravity, in which the gravitational action $L$ is given by an arbitrary function $f$ of the nonmetricity $Q$ and of the trace of the matter energy-momentum tensor $T$, so that…

General Relativity and Quantum Cosmology · Physics 2020-05-19 Yixin Xu , Guangjie Li , Tiberiu Harko , Shi-Dong Liang

We present an analysis of an $f(T, \mathcal{T})$ extension of the Teleparallel Equivalent of General Relativity, where $T$ denotes the torsion and $\mathcal{T}$ the trace of the energy-momentum tensor. This extension includes non--minimal…

General Relativity and Quantum Cosmology · Physics 2016-07-27 Diego Saez-Gomez , C. Sofia Carvalho , Francisco S. N. Lobo , Ismael Tereno

We study $f(R,T)$ gravity, in which the curvature $R$ appearing in the gravitational Lagrangian is replaced by an arbitrary function of the curvature and the trace $T$ of the stress-energy tensor. We focus primarily on situations where $f$…

General Relativity and Quantum Cosmology · Physics 2019-10-02 Sarah B. Fisher , Eric D. Carlson

The geometric trinity of gravity comprises three distinct formulations of general relativity: (i) the standard formulation describing gravity in terms of spacetime curvature, (ii) the teleparallel equivalent of general relativity describing…

General Relativity and Quantum Cosmology · Physics 2024-10-22 William J. Wolf , James Read , Quentin Vigneron

We consider scalar-tensor theories and reconstruct their potential U(\Phi) and coupling F(\Phi) by demanding a background LCDM cosmology. In particular we impose a background cosmic history H(z) provided by the usual flat LCDM…

Astrophysics · Physics 2011-05-19 S. Capozziello , S. Nesseris , L. Perivolaropoulos

The Lagrangian derivation of the Equations of Motion for topological static spherically symmetric metrics in $\mathcal F (R,G)$-modified gravity is presented and the related solutions are discussed. In particular, a new topological solution…

General Relativity and Quantum Cosmology · Physics 2013-04-16 Ratbay Myrzakulov , Lorenzo Sebastiani , Sergio Zerbini

The Noether-Bessel-Hagen theorem can be considered a natural extension of Noether Theorem to search for symmetries. Here, we develop the approach for dynamical systems introducing the basic foundations of the method. Specifically, we…

General Relativity and Quantum Cosmology · Physics 2021-02-03 Zbynek Urban , Francesco Bajardi , Salvatore Capozziello

In the context of f(R,T) theories of gravity, we study the evolution of scalar cosmological perturbations in the metric formalism. According to restrictions on the background evolution, a specific model within these theories is assumed in…

General Relativity and Quantum Cosmology · Physics 2013-06-20 F. G. Alvarenga , A. de la Cruz-Dombriz , M. J. S. Houndjo , M. E. Rodrigues , D. Sáez-Gómez

We examine the teleparallel formulation of non-minimally coupled scalar Einstein-Gauss-Bonnet gravity. In the teleparallel formulation, gravity is described by torsion instead of curvature, causing the usual Gauss-Bonnet invariant expressed…

General Relativity and Quantum Cosmology · Physics 2023-09-26 Sebastian Bahamonde , Daniela D. Doneva , Ludovic Ducobu , Christian Pfeifer , Stoytcho S. Yazadjiev

We generalize and unify the $f(R,T)$ and $f(R,L_m)$ type gravity models by assuming that the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar $R$, of the trace of the energy-momentum tensor $T$, and of the…

General Relativity and Quantum Cosmology · Physics 2021-07-28 Zahra Haghani , Tiberiu Harko

We extend the class of recently formulated scalar-nonmetricity theories by coupling a five-parameter nonmetricity scalar to a scalar field and considering a mixed kinetic term between the metric and the scalar field. The symmetric…

General Relativity and Quantum Cosmology · Physics 2018-10-23 Mihkel Rünkla , Ott Vilson

Nowadays, $f(R)$ theory has been one of the leading modified gravity theories to explain the current accelerated expansion of the universe, without invoking dark energy. It is of interest to find the exact cosmological solutions of $f(R)$…

General Relativity and Quantum Cosmology · Physics 2015-12-25 Hao Wei , Hong-Yu Li , Xiao-Bo Zou

We investigate gravitational waves generated in $f(Q,B)$ non-metric gravity, i.e., a theory of gravity described by a non-metric compatible connection, free of torsion and curvature. It is an extension of symmetric teleparallel gravity,…

General Relativity and Quantum Cosmology · Physics 2025-02-19 Salvatore Capozziello , Maurizio Capriolo , Gaetano Lambiase

Symmetric teleparallel gravity (STG) is a gravity theory which takes non-metricity tensor to describe gravity effects. In the STG framework, we study the conformal equivalent scalar-tensor theory of f(Q) model and calculate the cosmological…

General Relativity and Quantum Cosmology · Physics 2024-04-26 Dehao Zhao

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

The main purpose of this paper is to investigate the exact solutions of cylindrically symmetric spacetime in the context of $f(R,T)$ gravity [1], where $f(R,T)$ is an arbitrary function of Ricci scalar $R$ and trace of the energy momentum…

General Relativity and Quantum Cosmology · Physics 2015-07-01 M. Farasat Shamir , Zahid Raza

In this work a tetrad theory of gravity, invariant under conformal transformations, is investigated. The action of the theory is similar to the action of Maxwell's electromagnetism. The role of the electromagnetic gauge potential is played…

General Relativity and Quantum Cosmology · Physics 2012-06-28 J. W. Maluf , F. F. Faria

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
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