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Related papers: Quintom cosmological model and some possible solut…

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We consider the Noether Symmetry Approach for a cosmological model derived from a tachyon scalar field $T$ with a Dirac-Born-Infeld Lagrangian and a potential $V(T)$. Furthermore, we assume a coupled canonical scalar field $\phi$ with an…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Salvatore Capozziello , Mariafelicia De Laurentis , Ratbay Myrzakulov

We propose in this paper a quintom model of dark energy with a single scalar field $\phi$ given by the lagrangian ${\cal L}=-V(\phi)\sqrt{1-\alpha^\prime\nabla_{\mu}\phi\nabla^{\mu}\phi +\beta^\prime \phi\Box\phi}$. In the limit of…

High Energy Physics - Theory · Physics 2008-11-26 Yi-fu Cai , Mingzhe Li , Jian-Xin Lu , Yun-Song Piao , Taotao Qiu , Xinmin Zhang

Noether's theory offers us a useful tool to research the conserved quantities and symmetries of the modified gravity theories, among which the $f(T)$ theory, a generally modified teleparallel gravity, has been proposed to account for the…

General Relativity and Quantum Cosmology · Physics 2013-10-07 Han Dong , Jiaxin Wang , Xinhe Meng

We consider the symmetric teleparallel $f\left( Q\right) $-gravity in Friedmann--Lema\^{\i}tre--Robertson--Walker cosmology with nonzero spatial curvature. For a nonlinear $f\left( Q\right) $ model there exist always the limit of General\…

General Relativity and Quantum Cosmology · Physics 2023-10-09 Andronikos Paliathanasis

We summarize the use of Noether symmetries in Minisuperspace Quantum Cosmology. In particular, we consider minisuperspace models, showing that the existence of conserved quantities gives selection rules that allow to recover classical…

General Relativity and Quantum Cosmology · Physics 2013-08-07 Salvatore Capozziello , Mariafelicia De Laurentis

Recently, few cosmological models with additional non-Riemannian volume form(s) have been proposed. In this article we use Supernovae type Ia experimental data to test one of these models which provides a unified description of both dark…

General Relativity and Quantum Cosmology · Physics 2018-10-05 Denitsa Staicova , Michail Stoilov

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

It has been noticed that for a large class of cosmological models, the gauge fixing of the time-reparametrization invariance does not completely fix the clock. Instead, the system enjoys a surprising residual Noether symmetry under a…

General Relativity and Quantum Cosmology · Physics 2021-12-15 Jibril Ben Achour

We study the phase space of the quintom cosmologies for a class of exponential potentials. We combine normal forms expansions and the center manifold theory in order to describe the dynamics near equilibrium sets. Furthermore, we construct…

General Relativity and Quantum Cosmology · Physics 2018-09-24 Genly Leon , Andronikos Paliathanasis , Jorge Luis Morales-Martínez

This paper explores Noether and Noether gauge symmetries of anisotropic universe model in $f(R,T)$ gravity. We consider two particular models of this gravity and evaluate their symmetry generators as well as associated conserved quantities.…

General Physics · Physics 2017-05-24 M. Sharif , Iqra Nawazish

We address the group classification problem for gravitational field equations within the context of brane-world cosmology, considering the presence of a bulk scalar field. Our investigation revolves around a five-dimensional spacetime, with…

General Relativity and Quantum Cosmology · Physics 2023-10-10 Andronikos Paliathanasis

A model for a spatially flat homogeneous and isotropic Universe whose gravitational sources are a pressureless matter field and a tachyon field non-minimally coupled to the gravitational field is analyzed. Noether symmetry is used to find…

General Relativity and Quantum Cosmology · Physics 2010-04-30 Rudinei C. de Souza , Gilberto M. Kremer

We analyze the quantum supersymmetric cosmological FRW model with a scalar field, with a conditional probability density and the scalar field identified as time. The Hilbert space has a spinorial structure and there is only one consistent…

General Relativity and Quantum Cosmology · Physics 2016-03-23 C. Ramírez , V. Vázquez-Báez

We investigate the quantum cosmology of a closed spatially homogeneous and isotropic Friedmann-Lema\^itre-Robertson-Walker (FLRW) minisuperspace model with electromagnetic radiation as matter content. We solve the corresponding…

General Relativity and Quantum Cosmology · Physics 2022-07-15 S. Jalalzadeh

We discuss the Noether Symmetry Approach in the framework of Gauss-Bonnet cosmology showing that the functional form of the $F(R, {\cal G})$ function, where $R$ is the Ricci scalar and ${\cal G}$ is the Gauss-Bonnet topological invariant,…

General Relativity and Quantum Cosmology · Physics 2014-11-13 Salvatore Capozziello , Mariafelicia De Laurentis , Sergei D. Odintsov

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

Extended $f(R)$ theories of gravity have been investigated from the symmetry point of view. We briefly has been investigated Noether symmetry of two types of extended $f(R)$ theories: $f(R,T)$ theory, in which curvature is coupled non…

General Relativity and Quantum Cosmology · Physics 2018-10-09 D. Momeni , R. Myrzakulov , E. Güdekli

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 article in a generalization of our previous work, we investigate the dynamics of the non-local $F(R)$ gravity after casting it into local form. The non-singular bouncing behavior and quintom model of dark energy are achieved without…

General Relativity and Quantum Cosmology · Physics 2015-05-30 H. Farajollahi , F. Tayebi , F. Milani , M. Enayati

The basic idea of the LQC applies to every spatially homogeneous cosmological model, however only the spatially flat (so called $k=0$) case has been understood in detail in the literature thus far. In the closed (so called: k=1) case…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Lukasz Szulc , Wojciech Kaminski , Jerzy Lewandowski