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Related papers: Stability of $f(Q, B)$ Gravity via Dynamical Syste…

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In this work, we investigate the dynamics of bouncing cosmologies within the framework of Weyl-type $f(Q,T)$ gravity. Here, $Q$ represents the non-metricity of the space-time, is determined by the vector field $w_\mu$, while $T$ represents…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-25 A. Zhadyranova , M. Koussour , S. Bekkhozhayev

We propose an extension of the symmetric teleparallel gravity, in which the gravitational action $L$ is given by an arbitrary function $f$ of the nonmetricity $Q$ and of the trace of the matter energy-momentum tensor $T$, so that…

General Relativity and Quantum Cosmology · Physics 2020-05-19 Yixin Xu , Guangjie Li , Tiberiu Harko , Shi-Dong Liang

The dynamical aspects of some accelerating models are investigated in the framework of an extension of symmetric teleparllel gravity dubbed as f(Q,T) gravity. In this gravity theory, the usual Ricci tensor in the geometrical action is…

General Relativity and Quantum Cosmology · Physics 2021-07-28 Laxmipriya Pati , B. Mishra , S. K. Tripathy

This study offers a comprehensive reconstruction of $f(T)$ gravity model with three distinct non-linear as well as novel forms employing a hybrid scale factor to depict the expansion history of the universe starting from early decelerated…

General Relativity and Quantum Cosmology · Physics 2026-02-17 Suraj Kumar Behera , Pratik P. Ray

In this paper, we investigate a cosmological model based on viscous $f(R,T)$ gravity as a potential alternative to dark energy. This model incorporates bulk viscosity and is analyzed using an effective equation of state. We consider the…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-26 M. Koussour , A. Altaibayeva , S. Bekov , O. Donmez , S. Muminov , J. Rayimbaev

This work investigates the dynamical evolution of the universe within the framework of symmetric teleparallel $f(Q,\mathcal{T})$ gravity, where $Q$ is the non-metricity scalar and $\mathcal{T}$ is the trace of the energy-momentum tensor. We…

General Relativity and Quantum Cosmology · Physics 2026-05-19 S. H. Shekh , S. B. Thool , Pankaj Kumar , P. C. Kalan , R. M. Dhaigude

We present a new $f(Q)$ cosmological model capable of reproducing late-time acceleration, i.e. $f\left( Q\right) = \lambda_{0}\left( \lambda +Q\right) ^{n}$ by supporting certain parametrization of the Hubble parameter. By using…

General Relativity and Quantum Cosmology · Physics 2023-06-26 N. Myrzakulov , M. Koussour , Dhruba Jyoti Gogoi

A new kind of evolution for cyclic models in which the Hubble parameter oscillates and keeps positive has been explored in a specific $f(R,T)$ gravity reconstruction. A singularity-free cyclic universe with negative varying cosmological…

General Relativity and Quantum Cosmology · Physics 2019-02-11 Nasr Ahmed , Sultan Z. Alamri

The dynamics of perfect fluid as a source in the context of modified gravity, specifically $f(Q,T)$ gravity, are examined within the Friedmann-Lema\^itre-Robertson-Walker (FLRW) cosmological model. This gravity is a generic function of the…

General Relativity and Quantum Cosmology · Physics 2024-08-02 S. H. Shekh , Anirudh Pradhan , S. P. Gaikwad , K. R. Mule

Modified gravity theories can be used for the description of homogeneous and isotropic cosmological models through the corresponding field equations. These can be cast into systems of autonomous differential equations because of their sole…

General Relativity and Quantum Cosmology · Physics 2024-04-08 Christian G. Boehmer , Erik Jensko , Ruth Lazkoz

In this letter, we investigate cosmology within the framework of modified $f(Q, L_m)$ gravity using the non-linear model $f(Q, L_m) = -Q + \alpha L_m^n + \beta$, where $\alpha$, $\beta$, and $n$ are free parameters. The modified Friedmann…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-02 Y. Myrzakulov , Alnadhief H. A. Alfedeel , M. Koussour , S. Muminov , E. I. Hassan , J. Rayimbaev

We investigate the cosmological implications of $f(Q,C)$ gravity with $f(Q,C)=\alpha Q+\beta C$, where $Q$ is the non-metricity scalar and $C$ encapsulates cosmological expansion terms. Three parameterizations of the EoS for dark energy,…

General Relativity and Quantum Cosmology · Physics 2024-11-28 Amit Samaddar , S. Surendra Singh

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

Dynamical analysis of spherically symmetric collapsing star surrounding in locally anisotropic environment with expansion-free condition is presented in $f(R,T)$ gravity, where $R$ corresponds to Ricci scalar and $T$ stands for the trace of…

General Relativity and Quantum Cosmology · Physics 2015-04-21 Ifra Noureen , M. Zubair

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

We have probed a cosmological model in $f(R)$-gravity, which is a cubic equation in scalar curvature $R$. The terms arise due to nonlinear $f(R)$ function are treated as energy due to curvature inspired geometry. As a result, we find…

General Relativity and Quantum Cosmology · Physics 2023-05-03 G. K. Goswami , Rita Rani , Harshna Balhara , J. K. Singh

In this paper, we model the bounce phase, stability, and the reconstruction of the universe by non-minimal kinetic coupling. In the process, we obtained importance information about the energy density and the matter pressure of the universe…

General Relativity and Quantum Cosmology · Physics 2026-02-10 Alireza Amani , A. S. Kubeka , E. Mahichi

In this paper, we have considered a quadratic variation of the deceleration parameter ($q$) as a function of cosmic time ($t$) which describes a smooth transition from the decelerating phase of the Universe to an accelerating one and also…

General Relativity and Quantum Cosmology · Physics 2022-06-30 Ritika Nagpal , Shibesh Kumar Jas Pacif

In this paper, we have analyzed the geometrical and dynamical parameters of $\mathcal{F}(R, \mathcal{G})=\alpha R^2 \mathcal{G}^\beta$ cosmological model, ($R$, $\mathcal{G}$ being the Ricci scalar and Gauss-Bonnet invariant respectively),…

General Relativity and Quantum Cosmology · Physics 2023-10-11 Santosh V. Lohakare , Krishna Rathore , B. Mishra

We systematically investigate static plane symmetric configurations in $f(Q)$ gravity. For vacuum regions, we discuss the constancy of the nonmetricity scalar $Q$ and derive general vacuum solutions, which correspond effectively to…

General Relativity and Quantum Cosmology · Physics 2026-05-12 Jun-Qin Long , Rui-Hui Lin , Xiang-Hua Zhai