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Related papers: Topological acceleration in relativistic cosmology

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It has previously been shown heuristically that the topology of the Universe affects gravity, in the sense that a test particle near a massive object in a multiply connected universe is subject to a topologically induced acceleration that…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-06 Jan J. Ostrowski , Boudewijn F. Roukema , Zbigniew P. Bulinski

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

Current cosmological observations, when interpreted within the framework of a homogeneous and isotropic Friedmann-Lemaitre-Robertson-Walker (FLRW) model, strongly suggest that the Universe is entering a period of accelerating expansion.…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-22 Philip Bull , Timothy Clifton

The role of global topology in the dynamics of the Universe is poorly understood. Along with observational programmes for determining the topology of the Universe, some small theoretical steps have recently been made. Heuristic…

General Physics · Physics 2015-06-03 Boudewijn F. Roukema

Parameters that quantify the acceleration of cosmic expansion are conventionally determined within the standard Friedmann-Lemaitre-Robertson-Walker (FLRW) model, which fixes spatial curvature to be homogeneous. Generic averages of…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-15 Lawrence H. Dam , Asta Heinesen , David L. Wiltshire

In view of late-time cosmic acceleration, a dark energy cosmological model is revisited wherein Einstein's cosmological constant is considered as a candidate of dark energy. Exact solution of Einstein field equations (EFEs) is derived in a…

General Relativity and Quantum Cosmology · Physics 2019-11-22 S. K. J. Pacif , Md Salahuddin Khan , L. K. Paikroy , Shalini Singh

As an alternative to dark energy that explains the observed acceleration of the universe, it has been suggested that we may be at the center of an inhomogeneous isotropic universe described by a Lemaitre-Tolman-Bondi (LTB) solution of…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-04 Antonio Enea Romano , Misao Sasaki

The problem of cosmic acceleration and dark energy is one of the mysteries presently posed in the scientific society that general relativity has not been able to solve. In this work, we have considered alternative models to explain this…

General Relativity and Quantum Cosmology · Physics 2022-12-01 M. Koussour , N. Myrzakulov , S. H. Shekh , M. Bennai

The quantized Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) model minimally coupled to a free massless scalar field is studied and interpreted in the Bohm-de Broglie framework. We analyze the quantum bohmian trajectories corresponding to…

General Relativity and Quantum Cosmology · Physics 2016-11-09 E. Sergio Santini

The applicability of a linearized perturbed FLRW metric to the late, lumpy universe has been subject to debate. We consider in an elementary way the Newtonian limit of the Einstein equations with this ansatz for the case of structure…

General Relativity and Quantum Cosmology · Physics 2019-12-18 Andreas Finke

We construct a FLRW universe considering an anisotropic scaling between space and time at extremely high and low energies only. In this context, Friedmann equations contain an additional term arising from spatial curvature which implements…

General Relativity and Quantum Cosmology · Physics 2018-12-26 Rodrigo Maier , Ivano Damião Soares

We study the quantized Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) model minimally coupled to a free massless scalar field. In a previous paper, \cite{fab2}, solutions of this model were constructed as gaussian superpositions of…

General Relativity and Quantum Cosmology · Physics 2009-11-10 N. Pinto-Neto , E. Sergio Santini

An important open question in cosmology is the degree to which the Friedmann-Lemaitre-Robertson-Walker (FLRW) solutions of Einstein's equations are able to model the large-scale behaviour of the locally inhomogeneous observable universe. We…

General Relativity and Quantum Cosmology · Physics 2013-08-29 Timothy Clifton , Kjell Rosquist , Reza Tavakol

From a classical analysis, it is shown that the nondiffractive accelerating gravitational Airy wave packets are solutions of Einstein equations for their linearized tensor modes in a Friedmann-Lema\^itre-Robertson-Walker cosmological…

General Relativity and Quantum Cosmology · Physics 2025-06-25 Claudio Aravena-Plaza , Víctor Muñoz , Felipe A. Asenjo

We consider spatially homogeneous and isotropic Friedmann-Robertson-Walker (FRW) solutions of Milgrom's recently proposed class of bimetric theories of gravity. These theories have two different regimes, corresponding to high and low…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Timothy Clifton , Thomas G. Zlosnik

A Newtonian uniform ball expanding in empty space constitutes a common heuristic analogy for FLRW cosmology. We discuss possible implementations of the corresponding general-relativistic problem and a variety of new cosmological analogies…

General Relativity and Quantum Cosmology · Physics 2020-08-12 Valerio Faraoni , Farah Atieh

Accelerating cosmologies in extra dimensional spaces have been studied. These extra dimensional spaces are products of many spaces. The physical behaviors of accelerating cosmologies are investigated from Einstein's field equation in higher…

Astrophysics · Physics 2008-10-16 Han Siong Ch'ng

In the macroscopic gravity approach to the averaging problem in cosmology, the Einstein field equations on cosmological scales are modified by appropriate gravitational correlation terms. We study the averaging problem within the class of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. A. Coley , N. Pelavas

A solution of the (4+n)-dimensional vacuum Einstein equations is found for which spacetime is compactified on a compact hyperbolic manifold of time-varying volume to a flat four-dimensional FLRW cosmology undergoing accelerated expansion in…

High Energy Physics - Theory · Physics 2008-11-26 Paul K. Townsend , Mattias N. R. Wohlfarth

General relativistic entropic acceleration theory may explain the present cosmic acceleration from first principles without the need of introducing a cosmological constant. Following the covariant formulation of non-equilibrium phenomena in…

General Relativity and Quantum Cosmology · Physics 2021-10-20 Juan Garcia-Bellido , Llorenc Espinosa-Portales
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