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Related papers: The Lambert $W$ function: A newcomer in the Cosmol…

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We investigate the hypothesis that the evolution of the Universe can be described by a single dark fluid whose effective equation of state (EoS), $\omega_{\rm{eff}}$, is a linear combination of a logarithmic term and a power law term, both…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-30 Vipin Chandra Dubey , Subhajit Saha , Abdulla Al Mamon

We systematically study the evolution of the Friedmann-Robertson-Walker (FRW) universe coupled with a cosmological constant $\Lambda$ and a perfect fluid that has the equation of state $p=w\rho$, where $p$ and $\rho$ denote, respectively,…

It is well known that the canonical quantization of the Friedmann-Lema\^itre-Robertson-Walker (FLRW) filled with a perfect fluid leads to nonsingular universes which, for later times, behave as their classical counterpart. This means that…

General Relativity and Quantum Cosmology · Physics 2013-05-09 J. P. M. Pitelli , P. S. Letelier

We study the cosmological evolutions of the equation of state (EoS) for the universe in the homogeneous and isotropic Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) space-time. In particular, we reconstruct the cyclic universes by using the…

General Relativity and Quantum Cosmology · Physics 2014-01-14 Kazuharu Bamba , Kuralay Yesmakhanova , Koblandy Yerzhanov , Ratbay Myrzakulov

The origin of the accelerated expansion of the Universe remains an unsolved mystery in Cosmology. In this work we consider a spatially flat Friedmann-Robertson-Walker (FRW) Universe with non-relativistic matter and a single scalar field…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Remya Nair , Sanjay Jhingan , Deepak Jain

Recent observational indications of an accelerating universe enhance the interest in studying models with a cosmological constant. We investigate cosmological expansion (FRW metric) with $\Lambda>0$ for a general linear equation of state…

General Relativity and Quantum Cosmology · Physics 2016-08-31 A. S. Silbergleit

In this paper, we investigate the possibility that the Universe is driven by a single dark fluid described by a Lambert $W$ equation of state parameter, $w_{eff}$, which is essentially dependent on two parameters $\vartheta_{1}$ and…

General Relativity and Quantum Cosmology · Physics 2022-02-14 Abdulla Al Mamon , Subhajit Saha

Recently, a novel equation of state (EoS) parameter for dark energy has been introduced which deals with a special mathematical function, known as the Lambert$W$ function. In this paper, we study the effect on the growth of perturbations…

General Relativity and Quantum Cosmology · Physics 2021-06-11 Manisha Banerjee , Sudipta Das , Abdulla Al Mamon , Subhajit Saha , Kazuharu Bamba

In this paper, we present a comprehensive cosmological analysis within the framework of $f(R, \Sigma, T)$ gravity, a modified theory that incorporates nonlinear matter-geometry coupling via the inclusion of both the trace of the…

General Relativity and Quantum Cosmology · Physics 2025-11-24 S. H. Shekh , N. Myrzakulov , Anil Kumar Yadav , Anirudh Pradhan

Recent observational indications of an accelerating universe enhance the interest in studying models with a cosmological constant. We investigate cosmological expansion (FRW metric) with $\Lambda>0$ for a general linear equation of state…

Astrophysics · Physics 2009-11-07 A. S. Silbergleit

An explicit and complete set of constants of the motion are constructed algorithmically for Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) models consisting of an arbitrary number of non-interacting species. The inheritance of constants of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Kayll Lake

We present a new way describing the solution of the Einstein-scalar field theory with exponential potential $V\propto e^{\sqrt{6}\beta \phi/M_{Pl}}$ in spatially flat Friedmann-Robertson-Walker space-time. We introduced a new time variable,…

General Relativity and Quantum Cosmology · Physics 2013-12-10 Hyeong-Chan Kim

We study the classical and quantum models of a flat Friedmann-Robertson-Walker (FRW) space-time, coupled to a perfect fluid, in the context of the consensus and a gauge-fixed Lagrangian frameworks. It is shown that, either in the usual or…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Babak Vakili

In this paper we take matter source with non-linear Equation of state (EoS) that has produced non-singular Emergent cosmology for spatially flat universe in General Relativity and minimally coupled scalar field with two different potentials…

General Relativity and Quantum Cosmology · Physics 2023-10-23 Rikpratik Sengupta , B. C. Paul , M. Kalam , P. Paul , A. Aich

In the framework of a flat Friedmann-Lema{\^\i}tre-Robertson-Walker (FLRW) geometry, we present a nonsingular model (no big bang singularity at finite time) of our universe describing its evolution starting from its early inflationary era…

General Relativity and Quantum Cosmology · Physics 2016-04-20 Jaume de Haro , Jaume Amorós , Supriya Pan

In this article we perform dynamical analysis of a broad class of barotropic fluids in the spatially curved Friedmann-Robertson-Walker (FRW) spacetime background without considering the cosmological constant. The first part of our study…

General Relativity and Quantum Cosmology · Physics 2020-03-04 Morteza Kerachian , Giovanni Acquaviva , Georgios Lukes-Gerakopoulos

The cosmological application of a dark viscous fluid in a spatially flat Friedmann-Robertson-Walker (FRW) universe with a modified logarithmic equation of state (EoS), being an analogue of the equation associated with the isotropic…

General Relativity and Quantum Cosmology · Physics 2026-04-02 I. Brevik , A. V. Timoshkin

The time evolution of cosmological parameters in early Universe at the deconfinement transition is studied by an equation of state (EoS) which takes into account the finite baryon density and the background magnetic field. The non…

High Energy Physics - Phenomenology · Physics 2015-09-30 Paolo Castorina , Vincenzo Greco , Salvatore Plumari

By way of a complete integration of the Friedmann equations, in terms of observables, it is shown that for the cosmological constant $\Lambda > 0$ there exist non-flat FLRW models for which the total density parameter $\Omega$ remains $\sim…

Astrophysics · Physics 2009-11-10 Kayll Lake

Extending the approach developed by Ara\'ujo and Stoeger [1] and improved in Ara\'ujo {\it et al} [2], we have shown how to construct dust-filled $\Lambda \neq 0$ Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) cosmological models from FLRW…

Astrophysics · Physics 2009-02-20 M. E. Araujo , W. S. Stoeger , R. C. Arcuri , M. L. Bedran
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