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Related papers: Emergent scenario in the Einstein-Cartan theory

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We investigate stability of the Einstein static solution against homogeneous scalar, vector and tensor perturbations in the context of Rastall theory of gravity. We show that this solution in the presence of perfect fluid and vacuum energy…

General Relativity and Quantum Cosmology · Physics 2018-07-10 F. Darabi , K. Atazadeh , Y. Heydarzade

We consider static cosmological solutions along with their stability properties in the framework of a recently proposed theory of massive gravity. We show that the modifcation introduced in the cosmological equations leads to several new…

General Relativity and Quantum Cosmology · Physics 2012-07-27 Luca Parisi , Ninfa Radicella , Gaetano Vilasi

The purpose of this paper is to analyze the existence of static stable Einstein universe using inhomogeneous linear perturbations in the context of $f(R,T)$ gravity ($R$ and $T$ denote the scalar curvature and trace of the stress-energy…

General Relativity and Quantum Cosmology · Physics 2020-02-19 M. Sharif , Arfa Waseem

In the Emergent scenario, the Universe should evolve from a non-singular state replacing the typical singularity of General Relativity, for any initial condition. For the scalar field model in [1] we show that only a set of measure zero of…

General Relativity and Quantum Cosmology · Physics 2024-08-13 Molly Burkmar , Marco Bruni

We consider the existence and stability of the Einstein static universe under the Generalized Uncertainty Principle (GUP) effects. We show that this solution in the presence of perfect fluid with a minimal length is cyclically stable around…

General Relativity and Quantum Cosmology · Physics 2017-05-25 K. Atazadeh , F. Darabi

We study the static cosmological solutions and their stability at background level in the framework of massive bigravity theory with Friedmann-Robertson-Walker (FRW) metrics. By the modification proposed in the cosmological equations…

General Relativity and Quantum Cosmology · Physics 2017-05-17 M. Mousavi , F. Darabi

The emergent universe scenario is a proposal for resolving the Big Bang singularity problem in the standard Friedmann-Lemaitre-Robertson-Walker cosmology. In the context of this scenario, the Universe originates from a nonsingular static…

General Relativity and Quantum Cosmology · Physics 2021-07-14 Elham Ghorani , Yaghoub Heydarzade

Einstein--Cartan theory is a generalization of general relativity that introduces spacetime torsion. In this paper, we perform phase space analysis to investigate the evolution of the early universe in Einstein--Cartan theory. By studying…

General Relativity and Quantum Cosmology · Physics 2025-05-06 Qihong Huang , He Huang , Bing Xu , Kaituo Zhang

We explore the possibility of emergent cosmology using the effective potential formalism. We discover new models of emergent cosmology which satisfy the constraints posed by the cosmic microwave background (CMB). We demonstrate that, within…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-18 Satadru Bag , Varun Sahni , Yuri Shtanov , Sanil Unnikrishnan

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

We analyze the stability of the Einstein static universe in scalar-tensor theory of gravity, and find it can be stable against both scalar and tensor perturbations under certain conditions. By assuming the emergent scenario originating from…

General Relativity and Quantum Cosmology · Physics 2023-06-13 Qihong Huang , He Huang , Bing Xu

We investigate whether or not an Einstein Static universe is a solution to the cosmological equations in $f(R)$ gravity. It is found that only one class of $f(R)$ theories admits an Einstein Static model, and that this class is neutrally…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Rituparno Goswami , Naureen Goheer , Peter K. S. Dunsby

We consider alternative inflationary cosmologies in massive gravity with degenerate reference metrics and study the feasibilities of the emergent universe scenario, bouncing and cyclic universes. We focus on the construction of the Einstein…

General Relativity and Quantum Cosmology · Physics 2019-05-28 Shou-Long Li , H. Lü , Hao Wei , Puxun Wu , Hongwei Yu

In the field equations of Einstein-Cartan theory with cosmological constant a static spherically symmetric perfect fluid with spin density satisfying the Weyssenhoff restriction is considered. This serves as a rough model of space filled…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Christian G. Boehmer

In this work, we study the issue of the past and future cosmological singularities in the context of the fourth-order conformal Weyl gravity. In particular, we investigate the emergent universe scenario proposed by Ellis {\it et al}, and…

General Relativity and Quantum Cosmology · Physics 2020-06-02 Yaghoub Heydarzade

The Emergent Universe scenario is based on the assumption that the universe originates from a past-eternal Einstein static (ES) state, subsequently evolving toward an inflationary phase and a hot Big Bang era. Such models are appealing as…

General Relativity and Quantum Cosmology · Physics 2026-05-20 Pedro Labraña , Juan Ortiz

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 the realization of the emergent universe scenario in theories with natural UV cutoffs, namely a minimum length and a maximum momentum, quantified by a new deformation parameter in the generalized uncertainty principle. We…

General Relativity and Quantum Cosmology · Physics 2017-12-07 Mohsen Khodadi , Kourosh Nozari , Emmanuel N. Saridakis

We study Einstein static universes in the context of generic f(R) models. It is shown that Einstein static solutions exist for a wide variety of modified gravity models sourced by a barotropic perfect fluid with equation of state w=p/rho,…

General Relativity and Quantum Cosmology · Physics 2009-03-14 Sanjeev S. Seahra , Christian G. Boehmer

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