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Related papers: Stability and Space Phase Analysis in f(R) theory …

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In this paper, we have analyzed the stability of cylindrically symmetric collapsing object filled with locally anisotropic fluid in $f(R,T)$ theory, where $R$ is the scalar curvature and $T$ is the trace of stress-energy tensor of matter.…

General Physics · Physics 2018-11-15 M. Zubair , Hina Azmat , Ifra Noureen

We use a dynamical system approach to study the cosmological viability of $f(R,\mathcal{G})$ gravity theories. The method consists of formulating the evolution equations as an autonomous system of ODEs, using suitable variables. The…

General Relativity and Quantum Cosmology · Physics 2018-03-12 Simony Santos da Costa , Fernando V. Roig , Jailson S. Alcaniz , Salvatore Capozziello , Mariafelicia de Laurentis , Micol Benetti

This work is based on stability analysis of spherically symmetric collapsing star surrounding in locally anisotropic environment in $f(R,T)$ gravity, where $R$ is Ricci scalar and $T$ corresponds to the trace of energy momentum tensor.…

General Physics · Physics 2014-11-26 Ifra Noureen , M. Zubair

The energy conditions are derived in the context of $f(R,T)$ gravity, where $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor, which can reduce to the well-known conditions in $f(R)$ gravity and general relativity.…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Muhammad Sharif , Muhammad Zubair

Modified gravity is one of the most favorable candidates for explaining the current accelerating expansion of the Universe. In this regard, we study the viability of an alternative gravitational theory, namely $f(R,G)$, by imposing energy…

General Relativity and Quantum Cosmology · Physics 2014-01-30 K. Atazadeh , F. Darabi

In this study, we analyze the dynamics of the interaction between dark matter and curvature-driven dark energy in viable $f(R)$ gravity models using the framework of dynamical system analysis. We incorporate this interaction by introducing…

General Relativity and Quantum Cosmology · Physics 2024-03-11 Anirban Chatterjee , Rahul Roy , Sayantan Dey , Abhijit Bandyopadhyay

The stable critical points and their corresponding cosmology are derived in the teleparallel gravity with an added Gauss-Bonnet topological invariant term. We have analyzed the dynamics of the Universe by presenting two cosmological viable…

General Relativity and Quantum Cosmology · Physics 2023-12-12 S. A. Kadam , Santosh V Lohakare , B. Mishra

In this paper, we carry out a study of viable cosmological models in $f(R)$-gravity at the background level. We use observable parameters like $\Omega$ and $\gamma$ to form autonomous system of equations and show that the models under…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-28 Amna Ali , Radouane Gannouji , M. Sami , Anjan A. Sen

Dark energy models based on f(R) theory have been extensively studied in literature to realize the late time acceleration. In this paper, we have chosen a viable f(R) model and discussed its effects on the dynamical instability of…

General Relativity and Quantum Cosmology · Physics 2015-05-30 M. Sharif , H. Rizwana Kausar

In this paper, we derive the field equations of modified Gauss-Bonnet gravity termed as $f(R,G)$ gravity for the non-flat Friedmann-Robertson-Walker (FRW) spacetime. We utilize the dynamical system approach to study the cosmic dynamics of…

General Relativity and Quantum Cosmology · Physics 2025-01-22 Ashutosh Singh

A generic feature of viable exponential $F(R)$-gravity is investigated. An additional modification to stabilize the effective dark energy oscillations during matter era is proposed and applied to two viable models. An analysis on the future…

General Relativity and Quantum Cosmology · Physics 2015-09-21 K. Bamba , A. Lopez-Revelles , R. Myrzakulov , S. D. Odintsov , L. Sebastiani

Recently, a Friedmann-Robertson-Walker universe filled with various cosmological fluids has been considered by S.D. Odintsov et al. in [30] from phase space vantage point where various expressions for the Equation-of-State (EoS) parameter…

General Relativity and Quantum Cosmology · Physics 2021-02-24 Behzad Tajahmad , Hossein Motavalli

We construct a compact phase space for flat FLRW spacetimes with standard matter described by a perfect fluid with a barotropic equation of state for general f(R) theories of gravity, subject to certain conditions on the function f. We then…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Mohamed Abdelwahab , Rituparno Goswami , Peter K. S. Dunsby

In this manuscript, we have identified the dynamical instability constraints of a self-gravitating cylindrical object within the framework of $f(R,T)$ theory of gravity. We have explored the modified field equations and corresponding…

General Physics · Physics 2016-05-18 Z. Yousaf , M. Zaeem ul Haq Bhatti

In this paper, we have continued the work of Herrera \emph{et al.} \cite{herrera2012dynamical} in $f(G)$ gravitational theory. For this purpose, a spherically symmetric fluid exhibiting locally anisotropic pressure along with the energy…

General Relativity and Quantum Cosmology · Physics 2020-05-19 M. Z. Bhatti , Z. Yousaf , A. Khadim

A new cosmological model based on the de Sitter gravity is investigated by dynamical analysis and numerical discussions. Via some transformations, the evolution equations of this model can form an autonomous system with 8 physical critical…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-01 Xi-chen Ao , Xin-zhou Li , Ping Xi

We investigate equations of motion and future singularities of $f(R,T)$ gravity where $R$ is the Ricci scalar and $T$ is the trace of stress-energy tensor. Future singularities for two kinds of equation of state (barotropic perfect fluid…

General Relativity and Quantum Cosmology · Physics 2018-08-21 Behrouz Mirza , Fatemeh Oboudiat

The generalized Gauss-Bonnet theory, introduced by Lagrangian F(R,G), has been considered as a general modified gravity for explanation of the dark energy. G is the Gauss-Bonnet invariant. For this model, we seek the situations under which…

General Relativity and Quantum Cosmology · Physics 2009-09-01 M. Alimohammadi , A. Ghalee

In this paper, we examine the interacting dark energy model in $f(T)$ cosmology. We assume dark energy as a perfect fluid and choose a specific cosmologically viable form $f(T)= \beta\sqrt{T} $. We show that there is one attractor solution…

General Relativity and Quantum Cosmology · Physics 2012-11-30 Mubasher Jamil , Kuralay Yesmakhanova , Davood Momeni , Ratbay Myrzakulov

Within the limits of the present cosmological observations in f(R,T) gravity theory, we have analyzed a spherically symmetric space-time in 5D setting. The field equations have been carefully studied considering reasonable cosmological…

General Relativity and Quantum Cosmology · Physics 2020-10-28 Pheiroijam Suranjoy Singh , Kangujam Priyokumar Singh