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The evolution of the Universe is traditionally examined by monitoring how its material content evolves as it expands. This model of an isolated system is expressed as the equation of motion of the bulk but segmented into different epochs.…

General Relativity and Quantum Cosmology · Physics 2024-06-04 Bob Osano

This article explores the cosmological scenario of the universe in the context of the $f(T)$ power law model, where $T$ represent the torsion scalar. To obtain the deterministic solution of the field equations we parametrized the effective…

General Relativity and Quantum Cosmology · Physics 2024-11-11 S. R. Bhoyar , Yash B. Ingole

The R_h=ct Universe is a Friedmann-Robertson-Walker (FRW) cosmology which, like LCDM, assumes the presence of dark energy in addition to (baryonic and non-luminous) matter and radiation. Unlike LCDM, however, it is also constrained by the…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-25 Fulvio Melia

In a recent article, Faraoni proposed an alternative procedure to solve the Friedman-Lemaitre-Robertson-Walker (FLRW) cosmological equations. The basic result of that paper was obtained long ago through a different approach, which seems to…

Astrophysics · Physics 2015-06-24 J. A. S. Lima

The accelerating Friedmann flat universe, filled with an ideal fluid with a linear (oscillating) inhomogeneous equation of state (EoS) depending on time, is reviewed. The equations of motions are solved. It is shown that in some cases there…

General Relativity and Quantum Cosmology · Physics 2009-03-10 O. G. Gorbunova , A. V. Timoshkin

We study the dynamics of Friedmann-Lema\^itre-Robertson-Walker models where a dark energy component with a quadratic equation of state (EoS) nonlinearly interacts with cold dark matter. Thus, two energy scales naturally come into play:…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-06 Molly Burkmar , Marco Bruni , Thomas Waters

In the present work, we study the quantum cosmology description of a Friedmann-Robertson-Walker model in the presence of a stiff matter perfect fluid and a negative cosmological constant. We work in the Schutz's variational formalism and…

General Relativity and Quantum Cosmology · Physics 2015-05-28 G. Oliveira-Neto , G. A. Monerat , E. V. Corrêa Silva , C. Neves , L. G. Ferreira

In this paper we study a model of cosmic evolution, assuming that the different components of the universe could interact between them any time. An effective equation of state (EOS) for the universe has been used as well. A particular…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-17 Alberto C. Balfagon , Raul Ramirez-Satorras

The general relativistic cosmological Friedmann equations which describe how the scale factor of the universe evolves are expanded explicitly to include energy forms not usually seen. The evolution of the universe as predicted by the…

Astrophysics · Physics 2008-11-26 Robert J. Nemiroff , Bijunath Patla

We apply the idea of using a matter time gauge in quantum gravity to quantum cosmology. For the Friedmann-Lemaitre-Robertson-Walker (FLRW) Universe with dust and cosmological constant $\Lambda$, we show that the dynamics maps exactly to the…

General Relativity and Quantum Cosmology · Physics 2018-10-10 Masooma Ali , Syed Moeez Hassan , Viqar Husain

We consider the optical properties of Lindquist-Wheeler (LW) models of the Universe. These models consist of lattices constructed from regularly arranged discrete masses. They are akin to the Wigner-Seitz construction of solid state…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Timothy Clifton , Pedro G. Ferreira , Kane O'Donnell

A time-varying cosmological "constant" Lambda is consistent with Einstein's equation, provided matter and/or radiation is created or destroyed to compensate for it. Supposing an empty primordial universe endowed with a very large…

General Relativity and Quantum Cosmology · Physics 2014-11-17 R. Aldrovandi , J. P. Beltran Almeida , J. G. Pereira

In this manuscript, we present a number of fascinating explicit reconstructions for the $f(Q)$ gravity from the background of Friedmann-La\^imatre-Robertson-Walker (FLRW) evolution history. We find the more general functions of…

General Relativity and Quantum Cosmology · Physics 2022-10-25 Gaurav N. Gadbail , Sanjay Mandal , P. K. Sahoo

We present a new parameterization for the equation of state (EoS) $\omega_X=P_X/\rho_X$, which can reproduce a $f(R)$-like evolution with a precision between $[0.5\%-0.8\%]$ over the numerical solutions. Also, our proposal can render a…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-24 Luisa G. Jaime , Mariana Jaber , Celia Escamilla-Rivera

In the standard Friedmann-Lemaitre-Robertson-Walker (FLRW) approach to model the Universe the violation of the so-called energy conditions is related to some important properties of the Universe as, for example, the current and the…

Astrophysics · Physics 2016-03-28 M. P. Lima , S. D. P. Vitenti , M. J. Reboucas

We investigate the evolution of non vacuum Friedmann-Lema\^itre-Robertson-Walker (FLRW) with any spatial curvature in the context of Gauss-Bonnet gravity. The analysis employs a new method which enables us to explore the phase space of any…

General Relativity and Quantum Cosmology · Physics 2017-09-13 Sante Carloni , José P. Mimoso

In this paper we solve Friedmann equations by considering a universal media as a non-perfect fluid with bulk viscosity and is described by a general "gamma law" equation of state of the form $p= (\gamma -1) \rho + \Lambda(t)$, where the…

General Physics · Physics 2016-11-04 G. S. Khadekar , Saibal Ray , X. -H. Meng

The classical Friedmann-Lema\^itre equations are solved using a corrected version of Planck's radiation law. The function curves of the scale parameter a(t) and the variations with temperature a(T) and t(T) are given. It is shown that a…

General Relativity and Quantum Cosmology · Physics 2014-10-08 Rainer Collier

We describe the accelerated expansion of the late-time universe using a generalized equation of state (EoS) when account is taken of bulk viscosity. We assume a homogeneous and isotropic Friedmann-Robertson-Walker spacetime. Solutions of…

General Relativity and Quantum Cosmology · Physics 2019-08-05 I. Brevik , A. N. Makarenko , A. V. Timoshkin

In the symmetric teleparallel gravity framework, we study the cosmic dynamics of the universe with dark energy equation of state (EoS) parameter having non-linear forms. The non-metricity scalar induced by the dark energy EoS parameter…

General Relativity and Quantum Cosmology · Physics 2025-07-10 Romanshu Garg , G. P. Singh , Ashutosh Singh