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A complete analysis of the dynamics of the Hu-Sawicki modification to General Relativity is presented. In particular, the full phase-space is given for the case in which the model parameters are taken to be n=1, c1=1, and several stable de…

General Relativity and Quantum Cosmology · Physics 2015-11-03 Sulona Kandhai , Peter K. S. Dunsby

In this paper, we study the model of $f(T, B)$ gravity with viscous fluid in flat-FRW metric, in which $T$ and $B$ are torsion scalar and boundary term, respectively. We obtain the Friedmann equations in the framework of modified…

General Relativity and Quantum Cosmology · Physics 2019-09-02 A. Pourbagher , Alireza Amani

In this paper, we present a novel extension of massive gravity theory; the Brane-Chern-Simons massive gravity theory. We explore the cosmological implications of this theory by deriving the background equations and demonstrating the…

General Relativity and Quantum Cosmology · Physics 2024-11-28 Sobhan Kazempour , Amin Rezaei Akbarieh

We describe the ``deflationary'' evolution from an initial de Sitter phase to a subsequent Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) period as a specific non-equilibrium configuration of a self-interacting gas. The transition dynamics…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Winfried Zimdahl , Alexander B. Balakin

We study the dynamics of homogeneous and isotropic Friedmann-Lema\^itre-Robertson-Walker cosmological models with positive spatial curvature within the context of mimetic gravity theory by employing dynamical system techniques. Our analysis…

General Relativity and Quantum Cosmology · Physics 2024-09-18 Alberto Fritis , Daniel Villalobos-Silva , Yerko Vásquez , Carlos H. López-Caraballo , Juan Carlos Helo

In this work, we present a phase space analysis of a spatially flat Friedmann $-$Robertson$-$Walker (FRW) model in which the dark matter fluid is modeled as an imperfect fluid having bulk viscosity. The bulk viscosity is governed by the…

General Relativity and Quantum Cosmology · Physics 2019-01-23 Yoelsy Leyva

The Cosmological Principle is applied to a five-dimensional vacuum manifold. The general (non-trivial) solution is explicitly given. The result is a unique metric, parametrized with the sign of the space curvature ($k=0,\pm 1$) and the…

General Relativity and Quantum Cosmology · Physics 2019-08-14 Carles Bona , Miguel Bezares

In this paper we have examined the validity of the generalized second law of thermodynamics (GSLT) in an expanding Friedmann Robertson Walker (FRW) universe filled with different variants of Chaplygin gases. Assuming that the universe is a…

General Physics · Physics 2021-02-19 Samarjit Chakraborty , Sarbari Guha

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 implement a conformal time scale factor duality for Friedmann-Robertson-Walker cosmological models, which is consistent with the weak energy condition. The requirement for self-duality determines the equations of state for a broad class…

High Energy Physics - Theory · Physics 2017-03-15 U. Camara dS , A. A. Lima , G. M. Sotkov

The generalized Chaplygin gas model, characterized by the equation of state $p = - \frac{B}{\rho^{\alpha}}$, is investigated within the framework of a Robertson-Walker spacetime. The resulting field equations governing this model are highly…

General Relativity and Quantum Cosmology · Physics 2025-07-02 D Panigrahi

We examine the effect on cosmological evolution of adding a string motivated Gauss-Bonnet term to the traditional Einstein-Hilbert action for a (1 + 3) + d dimensional Friedman-Robertson- Walker (FRW) metric. By assuming that the additional…

High Energy Physics - Theory · Physics 2007-05-23 Keith Andrew , Brett Bolen , Chad A. Middleton

In this paper we have considered the Universe to be filled with Modified Gas and the Cosmological Constant $\Lambda$ to be time-dependent with or without the Gravitational Constant $G$ to be time-dependent. We have considered various…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Writambhara Chakraborty , Ujjal Debnath

We discuss flat Friedmann-Lemaitre-Robertson-Walker (FLRW) metric-affine cosmology where the metric and connection as well as the matter energy-momentum and hypermomentum all obey the symmetry of spatial homogeneity and isotropy. In…

General Relativity and Quantum Cosmology · Physics 2026-04-07 Ilaria Andrei , Damianos Iosifidis , Laur Järv , Margus Saal

We study the generalized Chaplygin gas (GCG) scenario in a modified gravity approach. That is, we impose that our universe has a pure dust configuration, and allow for a modification of gravity that yields a GCG specific scale factor…

Astrophysics · Physics 2009-11-10 T. Barreiro , A. A. Sen

In this paper we investigate to which extent noncommutativity, a intrinsically quantum property, may influence the Friedmann-Robertson-Walker cosmological dynamics at late times/large scales. To our purpose it will be enough to explore the…

General Relativity and Quantum Cosmology · Physics 2011-08-10 Octavio Obregon , Israel Quiros

This thesis focuses on late-time cosmic acceleration within modified theories of gravity, using various observational data sets and statistical analysis. The Universe is assumed to be spatially homogeneous and isotropic and is described by…

General Relativity and Quantum Cosmology · Physics 2025-03-05 Santosh V. Lohakare

In some interesting work of James Lidsey, the dynamics of Friedmann-Lema\^itre-Robertson-Walker (FLRW) cosmology with positive curvature and a perfect fluid matter source is shown to be modeled in terms of a time-dependent, harmonically…

Mathematical Physics · Physics 2014-11-21 Jennie D'Ambroise , Floyd L. Williams

The paper deals with $f(R)$ gravity theory in the background of inhomogeneous FLRW--type space time model. With proper choice of the inhomogeneous metric function it is possible to have an emergent scenario for the $f(R)$--cosmology.…

General Relativity and Quantum Cosmology · Physics 2018-11-14 Dipanjana Das , Sourav Dutta , Subenoy Chakraborty

In this paper, the dynamical system analysis has been performed to analyze the dynamical behavior of the Universe in $f(R,L_m,T)$ gravity with a scalar field. A well motivated potential function and the linear form of the functional…

General Relativity and Quantum Cosmology · Physics 2026-04-21 R. R. Panchal , Divya G. Sanjava , A. H. Hasmani , B. Mishra
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