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Related papers: Autonomous Dynamical System Approach for $f(R)$ Gr…

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The implications from the existence of a proper Homothetic Vector Field (HVF) on the dynamics of vacuum anisotropic models in $F(R)$ gravitational theory are studied. The fact that \emph{every} Spatially Homogeneous vacuum model is…

General Relativity and Quantum Cosmology · Physics 2017-03-28 Pantelis S. Apostolopoulos

In this paper, we perform the dynamical system analysis of the cosmological models framed in the extended teleparallel gravity, the $f (T, B)$ gravity. We use the mapping, $f(T, B)$ $\rightarrow$-$T$+$\tilde{f}(T, B)$, and define the…

General Relativity and Quantum Cosmology · Physics 2023-09-13 S. A. Kadam , Ninaad P. Thakkar , B. Mishra

Among the remaining viable theories that can successfully describe the late-time era is the $k$-Essence theory and in this work we study in detail the phase space of $k$-Essence $f(R)$ gravity in vacuum. This theory can describe in a viable…

General Relativity and Quantum Cosmology · Physics 2020-05-20 V. K. Oikonomou , N. Chatzarakis

We present a detailed investigation of the cosmological dynamics based on $\exp (-R/{\Lambda})$ gravity. We apply the dynamical system approach to both the vacuum and matter cases and obtain exact solutions and their stability in the finite…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. Abdelwahab , S Carloni , P K. S. Dunsby

The collapsing dynamics of relativistic fluid are explored in $f(R)$ gravity in a detailed systematic manner for the non-static spherically symmetric spacetime satisfying the equation of the conformal Killing vector. With quasi-homologous…

General Relativity and Quantum Cosmology · Physics 2024-10-03 Kazuharu Bamba , Z. Yousaf , M. Z. Bhatti , R. Nazer , Yuki Hashimoto

This is a first study of the cosmology of classical fractional gravity, a nonlocal proposal endowed with self-adjoint fractional d'Alembertian operators which serves as the basis for an ultraviolet-complete theory of quantum gravity. We…

General Relativity and Quantum Cosmology · Physics 2026-05-01 Iván Salvador-García , Gianluca Calcagni

Two accelerating cosmological models are presented in symmetric teleparallel $f(Q)$ gravity, $Q$ be the non-metricity. The models are constructed based on the assumptions of two different functional forms of $f(Q)$ and a dynamically…

General Relativity and Quantum Cosmology · Physics 2022-05-25 S. A. Narawade , Laxmipriya Pati , B. Mishra , S. K. Tripathy

In this paper we undertake the modified theory of gravity f(R,T) where R and T are the Ricci scalar and the trace of the energy momentum tensor, respectively. Imposing the conservation of the energy momentum tensor, we obtain a model about…

General Relativity and Quantum Cosmology · Physics 2015-06-30 E. H. Baffou , A. V. Kpadonou , M. E. Rodrigues , M. J. S. Houndjo , J. Tossa

For higher-derivative f(R) gravity where R is the Ricci scalar, a class of models is proposed which produce viable cosmology different from the LambdaCDM one at recent times and satisfy cosmological, Solar system and laboratory tests. These…

Astrophysics · Physics 2009-07-09 Alexei A. Starobinsky

To find more deliberate f(R,T) cosmological solutions, we proceed our previous paper further by studying some new aspects of the considered models via investigation of some new cosmological parameters/quantities to attain the most…

General Relativity and Quantum Cosmology · Physics 2017-05-23 Hamid Shabani , Mehrdad Farhoudi

We investigated a flat multidimensional cosmological model in Gauss-Bonnet gravity in presence of a matter in form of perfect fluid. We found analytically new stationary regimes (these results are valid for arbitrary number of spatial…

General Relativity and Quantum Cosmology · Physics 2015-03-13 I. V. Kirnos , S. A. Pavluchenko , A. V. Toporensky

Many different forms of the de Sitter metric in different coordinate systems are used in the general relativity literature. Two of them are the most common, the static form and the cosmological (exponentially expanding) form. The staticity…

General Relativity and Quantum Cosmology · Physics 2015-04-01 M. Nouri-Zonoz , J. Koohbor , H. Ramezani-Aval

In this article, we considered the bulk viscous fluid in the formalism of modified gravity in which the general form of a gravitational action is $f(R, T)$ function, where $R$ is the curvature scalar and $T$ is the trace of the energy…

General Relativity and Quantum Cosmology · Physics 2017-08-02 G. C. Samanta , R. Myrzakulov

We have investigated some bouncing cosmological models in an isotropic and homogeneous space time with the F(R) theory of gravity. Two functional forms of F(R) have been investigated with a bouncing scale factor. The dynamical parameters…

General Relativity and Quantum Cosmology · Physics 2024-03-21 A. S. Agrawal , S. Mishra , S. K. Tripathy , B. Mishra

In this article, we examine the dynamical evolution of flat FRW cosmological model in $f(R, L_m)$ gravity theory. We consider the general form of $f(R, L_m)$ defined as $f(R, L_m) = \Lambda + \frac{\alpha}{2} R + \beta L_m^n$, where…

General Relativity and Quantum Cosmology · Physics 2025-02-14 Aman Shukla , Rakesh Raushan , Raghavendra Chaubey

In this paper, we have performed the dynamical system analysis of $f(T)$ gravity cosmological models at both background and perturbation levels. We have presented three models pertaining to three distinct functional forms of $f(T)$. The…

General Relativity and Quantum Cosmology · Physics 2024-03-20 L. K. Duchaniya , Kanika Gandhi , B. Mishra

Several authors have argued that self-consistent $f(R)$ gravity models distinct from $\Lambda $CDM are almost ruled out. Confronting such claims, we present a particular two-parameter $f(R)$ model that: (a) is cosmologically viable and…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-18 V Miranda , Sergio E. Joras , Ioav Waga , Miguel Quartin

We present a unified dynamical systems framework for spatially flat FLRW cosmology in $f(Q)$ gravity, covering all three connection branches via a single set of Hubble-normalised variables without fixing $f(Q)$ \textit{a priori}. This…

General Relativity and Quantum Cosmology · Physics 2025-12-17 Jibitesh Dutta , Wompherdeiki Khyllep , Saikat Chakraborty , Daniele Gregoris , Khamphee Karwan

We study mimetic $F(R)$ gravity with potential and Lagrange multiplier constraint. In the context of these theories, we introduce a reconstruction technique which enables us to realize arbitrary cosmologies, given the Hubble rate and an…

General Relativity and Quantum Cosmology · Physics 2016-02-17 S. D. Odintsov , V. K. Oikonomou

Motivated by the fact that cosmological models based on $f(Q)$ gravity are very efficient in fitting observational datasets at both background and perturbation levels, we perform a combined dynamical system analysis of both background and…

General Relativity and Quantum Cosmology · Physics 2023-02-22 Wompherdeiki Khyllep , Jibitesh Dutta , Emmanuel N. Saridakis , Kuralay Yesmakhanova