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The general theory of relativity is the most popular theory to describe the dynamics of a system (especially the Universe) under gravity. In this framework, the solution of the Einstein field equation under curved space-time yields the…

General Relativity and Quantum Cosmology · Physics 2024-02-06 Subhayan Maity , Manojit Das

We present a Friedmann-Robertson-Walker (FRW) quantum cosmological model within the framework of Finslerian geometry. In this work, we consider a specific fluid. We obtain the corresponding Wheeler-DeWitt equation as the usual constraint…

General Physics · Physics 2019-11-04 S S De , Farook Rahaman , Nupur Paul

The theoretical and observational consequences of thermodynamics of open systems, which allow particle creation are investigated in modified $f(R,T)$ ($R$ is the Ricci scalar and $T$ is the trace of energy-momentum tensor) theory of gravity…

General Relativity and Quantum Cosmology · Physics 2014-08-26 C. P. Singh , Vijay Singh

Assuming that higher dimensions existed in the early stages of the universe where the evolution was inflationary, we construct an open, singularity-free, spatially homogeneous and isotropic cosmological model to study the effects of…

Astrophysics · Physics 2009-11-10 Koray Karaca , Selcuk Bayin

We develop a cosmological theory in which the evolution of the universe is controlled by the cosmological constant and dominated by the associated vacuum energy. The universe starts as a classical de Sitter space with an infinite effective…

General Physics · Physics 2023-03-21 J. M. Greben

It is shown that the decomposition theorems of York, Stewart and Walker for symmetric spatial second-rank tensors, such as the perturbed metric tensor and perturbed Ricci tensor, and the spatial fluid velocity vector imply that, for open,…

General Relativity and Quantum Cosmology · Physics 2021-03-09 P. G. Miedema

We consider a $D$-dimensional cosmological model with a dilaton field and two $(D-d-1)$-form field strengths which have nonvanishing fluxes in extra dimensions. Exact solutions for the model with a certain set of couplings are obtained by…

High Energy Physics - Theory · Physics 2018-09-24 Nahomi Kan , Masashi Kuniyasu , Kiyoshi Shiraishi , Kohjiroh Takimoto

Using an approach that treats the Ricci scalar itself as a degree of freedom, we analyze the cosmological evolution within an f(R) model that has been proposed recently (exponential gravity) and that can be viable for explaining the…

General Relativity and Quantum Cosmology · Physics 2012-11-02 Luisa Jaime , Marcelo Salgado , Leonardo Patino

The intention of our paper is to provide a pedagogical application of geometric algebra to a particularly well-investigated system: We formulate the geometric and dynamical properties of Friedmann-Robertson-Walker spacetimes within the…

General Relativity and Quantum Cosmology · Physics 2025-09-10 Pablo Banon Perez , Bjoern Malte Schaefer , Maarten DeKieviet

We present the method of describing an evolution in quantum cosmology in the framework of the reduced phase space quantization of loop cosmology. We apply our method to the flat Friedman-Robertson-Walker model coupled to a massless scalar…

General Relativity and Quantum Cosmology · Physics 2012-03-06 Jakub Mielczarek , Wlodzimierz Piechocki

We study a $(4+D)$-dimensional Kaluza-Klein cosmology with a Robertson-Walker type metric having two scale factors $a$ and $R$, corresponding to $D$-dimensional internal space and 4-dimensional universe, respectively. By introducing an…

General Relativity and Quantum Cosmology · Physics 2009-02-12 F. Darabi

The methods of dynamical systems have found wide applications in cosmology, with focus either upon inflation or upon the passage into dark energy era. In this paper, we endeavor to capture the whole history of the universe into a dynamical…

General Relativity and Quantum Cosmology · Physics 2020-07-15 Jibitesh Dutta , Laur Jarv , Wompherdeiki Khyllep , Sulev Tokke

We review the evolution of a spatially homogeneous and isotropic universe described by a Friedmann-Robertson-Walker spacetime filled with a collisionless, neutral, simple, massive gas. The gas is described by a one-particle distribution…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Francisco Astorga , Olivier Sarbach , Thomas Zannias

We develop a stochastic formulation of cosmology in the early universe, after considering the scatter in the redshift-apparent magnitude diagram in the early epochs as an observational evidence for the non-deterministic evolution of early…

Astrophysics · Physics 2015-06-24 C. Sivakumar , Moncy V. John , K. Babu Joseph

Formulae are presented for the linear growth factor D/a and its logarithmic derivative dlnD/dlna in expanding Friedmann-Robertson-Walker Universes with arbitrary matter and vacuum densities. The formulae permit rapid and stable numerical…

Astrophysics · Physics 2009-10-31 A. J. S. Hamilton

We show that the equations of motion governing the evolution of a collisionless gravitating system of particles in an expanding universe can be cast in a form which is almost independent of the cosmological density parameter, $\Omega$, and…

Astrophysics · Physics 2020-11-25 Adi Nusser , Jörg M. Colberg

We consider the cosmological evolution in an osculating point Barthel-Randers type geometry, in which to each point of the space-time manifold an arbitrary point vector field is associated. This Finsler type geometry is assumed to describe…

General Relativity and Quantum Cosmology · Physics 2021-08-23 Rattanasak Hama , Tiberiu Harko , Sorin V. Sabau , Shahab Shahidi

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

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 paper we exploit the theory of the dynamical systems to study the dynamics of the standard cosmological model of the universe, which is known as the $\Lambda$CDM model. We assume that the matter content in our universe consists of…

General Physics · Physics 2022-09-07 Danijela Branković , Žarko Mijajlović
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