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Process of formation of the universe with its further expansion in the first evolution stage is investigated in the framework of Friedmann-Robertson-Walker metrics on the basis of quantum model, where a new type of matter is introduced,…

General Relativity and Quantum Cosmology · Physics 2013-01-17 Sergei P. Maydanyuk

In this work we present some cosmologically relevant solutions using the spatially flat Friedmann-Lemaitre-Robertson-Walker (FLRW) spacetime in metric $f(R)$ gravity where the form of the gravitational Lagrangian is given by…

General Relativity and Quantum Cosmology · Physics 2018-10-17 Pritha Bari , Kaushik Bhattacharya , Saikat Chakraborty

We investigate the general relativistic dynamics of Robertson-Walker models with a non-linear equation of state (EoS), focusing on the quadratic case P = P_0 + \alpha \rho + \beta \rho^2. This may be taken to represent the Taylor expansion…

Astrophysics · Physics 2008-12-18 Kishore N. Ananda , Marco Bruni

We study the Friedmann-Robertson-Walker cosmological model to investigate non-smooth curvatures associated with multiple discontinuities involved in the evolution of the universe, by exploiting Lorentzian warped product scheme. Introducing…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Soon-Tae Hong

In this study, we investigated the effects of incorporating barotropic fluids on cosmological solutions within the general relativity (GR) framework. We proposed a modified version of the barotropic fluid with the EoS, $p=\zeta _0 \rho…

General Relativity and Quantum Cosmology · Physics 2025-04-29 Rajdeep Mazumdar , Mrinnoy M. Gohain , Kalyan Bhuyan

We investigate the late time acceleration of the universe in the context of the Stephani model. This solution generalizes those of Friedmann-Lemaitre-Robertson-Walker (FLRW) in such a way that the spatial curvature is a function of of time.…

General Relativity and Quantum Cosmology · Physics 2015-02-26 S. Sedigheh. Hashemi , S. Jalalzadeh , N. Riazi

We demonstrate two periodic or quasi-periodic generalizations of the Chaplygin gas (CG) type models to explain the origins of dark energy as well as dark matter by using the Weierstrass $\wp(t)$, $\sigma(t)$ and $\zeta(t)$ functions with…

General Relativity and Quantum Cosmology · Physics 2012-11-22 Kazuharu Bamba , Ujjal Debnath , Kuralay Yesmakhanova , Petr Tsyba , Gulgasyl Nugmanova , Ratbay Myrzakulov

The evolution of spatially homogeneous and isotropic cosmological models containing a perfect fluid with equation of state p=w\rho\ and a cosmological constant \Lambda\ is investigated for arbitrary combinations of w and \Lambda, using…

Physics Education · Physics 2012-09-19 Sebastiano Sonego , Vittorino Talamini

The present paper deals with the dynamics of spatially flat Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmological model with a time varying cosmological constant $\Lambda$ where $\Lambda$ evolves with the cosmic time (t) through the…

General Relativity and Quantum Cosmology · Physics 2022-10-19 Chingtham Sonia , S. Surendra Singh

In this paper, we examine the universe's expansion in $ f(R, L_{m}) $ gravity for a particular form of $ f(R, L_{m})=\frac{R}{2}+L_{m}^{n}$. The field equations for flat FLRW metric with matter Lagrangian $ L_{m}=\rho$ are derive. Hubble…

General Relativity and Quantum Cosmology · Physics 2025-02-12 Romanshu Garg , G. P. Singh , Ashwini R Lalke , Saibal Ray

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

There are so many ideas that potentially explain the dark energy phenomenon, current research is focusing on a more in-depth analysis of the potential effects of modified gravity on both local and cosmic scales. In this paper we have…

General Relativity and Quantum Cosmology · Physics 2025-11-24 S. H. Shekh , Hira Sohail , Irfan Mahmood , Allah Ditta , Anil Kumar Yadav

This paper investigates the thermodynamic evolution of the universe within the framework of a quadratic equation of state (EoS). Building upon the basis of the quadratic EoS model, as a phenomenological extension to dark energy models, we…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-28 A. Shahriar , M. Abbasiyan-Motlaq , M. Mohsenzadeh , E. Yusofi

In the framework of Lorentzian warped products, we study the Friedmann-Robertson-Walker cosmological model to investigate non-smooth curvatures associated with multiple discontinuities involved in the evolution of the universe. In…

Mathematical Physics · Physics 2009-11-10 Jaedong Choi , Soon-Tae Hong

This study considers the specific case of a flat, minimally coupled to gravity, quintessence cosmology with a dark energy quartic polynomial potential that has the same mathematical form as the Higgs potential. Previous work on this case…

General Relativity and Quantum Cosmology · Physics 2024-09-12 Rodger I. Thompson

We investigate the cosmological consequences of the modified Friedmann equations when the entropy associated with the apparent horizon, given by Barrow entropy, $S\sim A^{1+\delta/2}$, where $0\leq\delta\leq1$, represents the amount of the…

General Relativity and Quantum Cosmology · Physics 2023-01-18 Ahmad Sheykhi

In the context of f(R, T) gravity theory for the flat Friedmann Lemaitre Robertson Walker (FLRW) model, the accelerating expansion of the universe is investigated using a specific form of the emergent Hubble parameter. Datasets from H(z),…

General Relativity and Quantum Cosmology · Physics 2025-01-16 N. Myrzakulov , S. H. Shekh , Anirudh Pradhan , Archana Dixit

We apply the dynamical systems tools to study the (linear) dynamics of Friedmann-Robertson-Walker universes that are fuelled by non-linear electrodynamics. We focus, mainly, in two particular models. In the first model the cosmic evolution…

General Relativity and Quantum Cosmology · Physics 2009-05-08 Ricardo Garcia-Salcedo , Tame Gonzalez , Claudia Moreno , Israel Quiros

A review on spatially flat D-dimensional Friedmann-Robertson-Walker (FRW) model of the universe has been performed. Some standard parameterizations of the equation of state parameter of the Dark Energy models are proposed and the…

General Relativity and Quantum Cosmology · Physics 2019-03-26 Tanwi Bandyopadhyay , Ujjal Debnath

We discuss FRW universe with time-dependent EoS dark fluid which leads to multiple de Sitter space. This model (as well as its scalar-tensor version) may be considered as some classical analog of cosmological landscape. The universe…

High Energy Physics - Theory · Physics 2008-11-26 Shin'ichi Nojiri , Sergei D. Odintsov