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Related papers: The Instabilities of Bianchi Type IX Einstein Stat…

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This paper explores stability of the Einstein universe against linear homogeneous perturbations in the background of $f(\mathcal{G},T)$ gravity. We construct static as well as perturbed field equations and investigate stability regions for…

General Relativity and Quantum Cosmology · Physics 2017-07-26 M. Sharif , Ayesha Ikram

In this work we study the stability of the Jordan-Brans-Dicke (JBD) static universe. This is motivated by the possibility that the universe might have started out in an asymptotically JBD static state, in the context of the so called…

General Relativity and Quantum Cosmology · Physics 2009-07-22 Sergio del Campo , Ramon Herrera , Pedro Labrana

We consider fluctuations in a perfect irrotational fluid coupled to gravity in an Einstein static universe background. We show that the homogeneous linear perturbations of the scalar and metric fluctuations in the Einstein static universe…

General Relativity and Quantum Cosmology · Physics 2009-11-10 B. Losic , W. G. Unruh

In the present work we consider the existence and stability of Einstein static {\sf ES} Universe in Brans-Dicke ({\sf BD}) theory with non-vanishing spacetime torsion. In this theory, torsion field can be generated by the {\sf BD} scalar…

General Physics · Physics 2019-03-26 Hamid Shabani , Amir Hadi Ziaie

Loop Quantum Cosmology strongly modifies the high-energy dynamics of Friedman-Robertson-Walker models and removes the big-bang singularity. We investigate how LQC corrections affect the stability properties of the Einstein static universe.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Luca Parisi , Marco Bruni , Roy Maartens , Kevin Vandersloot

This paper analyzes the stability of the closed Einstein static universe by using linear homogeneous perturbations in the framework of energy-momentum squared gravity. This newly developed proposal resolves the primordial singularity and…

General Relativity and Quantum Cosmology · Physics 2021-08-25 M. Sharif , M. Zeeshan Gul

This paper investigates the existence and stability of Einstein universe in the context of $f(R,T,Q)$ gravity, where $Q=R_{\mu\nu}T^{\mu\nu}$. Considering linear homogeneous perturbations around scale factor and energy density, we formulate…

General Relativity and Quantum Cosmology · Physics 2018-12-19 M. Sharif , Arfa Waseem

In this paper, we describe the dynamics of a Bianchi Type V vacuum universe with an arbitrary cosmological constant. We begin by using an orthonormal frame approach to write Einstein's field equations as a coupled system of first-order…

General Relativity and Quantum Cosmology · Physics 2017-04-12 Ikjyot Singh Kohli

Stability of the Einstein static universe versus the linear scalar, vector and tensor perturbations is investigated in the context of deformed Ho\v{r}ava-Lifshitz cosmology inspired by entropic force scenario. A general stability condition…

General Relativity and Quantum Cosmology · Physics 2017-02-14 Y. Heydarzade , M. Khodadi , F. Darabi

We discuss the problem of the stability of the isotropy of the universe in the space of ever-expanding spatially homogeneous universes with a compact spatial topology. The anisotropic modes which prevent isotropy being asymptotically stable…

General Relativity and Quantum Cosmology · Physics 2008-11-26 John D. Barrow , Hideo Kodama

The stability of the Einstein static universe against the homogeneous scalar perturbations in $f(T)$ gravity is analyzed. Both the spatial closed and open universes are considered. We find that the stable Einstein static solutions exist in…

General Relativity and Quantum Cosmology · Physics 2011-10-05 Puxun Wu , Hongwei Yu

We investigate stability of the Einstein static universe against the scalar, vector and tensor perturbations in the context of induced matter brane gravity. It is shown that in the framework of this model, the Einstein static universe has a…

General Relativity and Quantum Cosmology · Physics 2015-04-22 Y. Heydarzade , F. Darabi

By rescaling the Gauss-Bonnet (GB) coupling constant $\alpha \rightarrow \alpha/(D-4)$ and considering the $D \rightarrow 4$ limit, the GB gravity gives rise to nontrivial modification of general relativity in four dimensions. In this work,…

General Relativity and Quantum Cosmology · Physics 2020-04-14 Shou-Long Li , Puxun Wu , Hongwei Yu

The emergent mechanism provides a possible way to resolve the big bang singularity problem by assuming that our universe originates from the Einstein static (ES) state. Thus, the existence of a stable ES solution becomes a very crucial…

General Relativity and Quantum Cosmology · Physics 2018-02-14 Qihong Huang , Puxun Wu , Hongwei Yu

Stability analysis of the Bianchi type I universe in pure gravity theory is studied in details. We first derive the non-redundant field equation of the system by introducing the generalized Bianchi type I metric. This non-redundant equation…

High Energy Physics - Theory · Physics 2009-11-07 W. F. Kao

Recently, Horava proposed a power counting renormalizable theory for (3+1)-dimensional quantum gravity, which reduces to Einstein gravity with a non-vanishing cosmological constant in IR, but possesses improved UV behaviors. In this work,…

General Relativity and Quantum Cosmology · Physics 2011-02-09 Christian G. Boehmer , Francisco S. N. Lobo

Oscillating phases in Bianchi type IX anisotropic universes are obtained as linearized solutions of Einstein-Cartan theory of gravity.Instead of making use of Weyssenhoff spinning fluids we addopt axionic torsion matter where the torsion…

Astrophysics · Physics 2007-05-23 L. C. Garcia de Andrade , G. A. Monerat

We consider the classical linear stability of a static universe filled with a non-interacting mixture of isotropic radiation and a ghost scalar field. Unlike the conventional Einstein static model, this cosmology is stable against…

General Relativity and Quantum Cosmology · Physics 2009-11-19 John D Barrow , Christos G Tsagas

The theoretical description of compact structures that share some key features with mass varying particles allows for a simple analysis of equilibrium and stability for massive stellar bodies. We investigate static, spherically symmetric…

General Relativity and Quantum Cosmology · Physics 2010-01-05 Alex E. Bernardini , O. Bertolami

The stability of an Einstein static universe in the DGP braneworld scenario is studied in this paper. Two separate branches denoted by $\epsilon=\pm1$ of the DGP model are analyzed. Assuming the existence of a perfect fluid with a constant…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Kaituo Zhang , Puxun Wu , Hongwei Yu