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相关论文: Stability of the flat FLRW metric in $f(T)$ gravit…

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We study a cosmological model in Rastall's theory of gravity in the framework of the flat FLRW metric. We formulate the value of the Hubble parameter, which contains two model parameters, $ \alpha $ and $ j $. Employing the Markov Chain…

广义相对论与量子宇宙学 · 物理学 2024-04-30 Shaily , Akanksha Singh , J. K. Singh , Saddam Hussain , Ratbay Myrzakulov

The $f(R)$ theory of gravitation developed perturbatively around the general theory of relativity with cosmological constant (the \text{$\Lambda$}CDM model) in a flat FLWR geometry is considered. As a result, a general explicit cosmological…

广义相对论与量子宇宙学 · 物理学 2025-02-25 Pham Van Ky , Nguyen Thi Hong Van , Nguyen Anh Ky

We examine in this paper the stability analysis in $f(R; T; R_{\mu\nu}T^{\mu\nu})$ modified gravity, where $R$ and $T$ are the Ricci scalar and the trace of the energy-momentum tensor, respectively. By considering the flat Friedmann…

广义相对论与量子宇宙学 · 物理学 2016-12-15 E. H. Baffou , M. J. S. Houndjo , J. Tossa

Our objective in this paper is to study the late-time behavior of the universe in a model resulting from a parametrization of the Hubble parameter ($H$) in $f(Q,T)$ gravity. We have considered the flat Friedmann-Lemaitre-Robertson-Walker…

广义相对论与量子宇宙学 · 物理学 2023-04-19 Viraj Kalsariya , Shibesh Kumar Jas Pacif

The present paper deals with the dynamics of spatially flat Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmological model with a time varying cosmological constant $\Lambda$ where $\Lambda$ evolves with the cosmic time (t) through the…

广义相对论与量子宇宙学 · 物理学 2022-10-19 Chingtham Sonia , S. Surendra Singh

The Hubble constant tension problem is analysed in the framework of a class of modified gravity, the so-called $F(R)$ gravity. To do so, we explore two models: an exponential and a power-law $F(R)$ gravities, which includes an early dark…

广义相对论与量子宇宙学 · 物理学 2021-03-24 Sergei D. Odintsov , Diego Sáez-Chillón Gómez , German S. Sharov

We explore the cosmological dynamics of a teleparallel Gauss-Bonnet gravity model defined by the torsion scalar $T$ and the torsion-based Gauss-Bonnet invariant $T_{\mathcal{G}}$, deriving modified Friedmann equations for a flat FLRW…

广义相对论与量子宇宙学 · 物理学 2026-01-16 Santosh V. Lohakare , S. K. Maurya , Aaisha Al Qassabi , B. Mishra

We investigate a spatially flat FLRW cosmological model in the framework of modified gravity described by the function \( f(R, L_m) = \alpha R + L_m^\beta + \gamma \), where \( L_m \) is the matter Lagrangian density. The modified Friedmann…

广义相对论与量子宇宙学 · 物理学 2026-02-05 G. K. Goswami , Anirudh Pradhan , Syamala Krishnannair

In this paper, we study the model of $f(T, B)$ gravity with viscous fluid in flat-FRW metric, in which $T$ and $B$ are torsion scalar and boundary term, respectively. We obtain the Friedmann equations in the framework of modified…

广义相对论与量子宇宙学 · 物理学 2019-09-02 A. Pourbagher , Alireza Amani

We study an isotropic flat FLRW-model in Scale-covariant theory of gravity $ f_{\gamma \delta}(\phi) $ \cite{Canuto:1977zz} which is explained in terms of ordinary and covariant differentiation of scalar field $ \phi $. As we know the…

广义相对论与量子宇宙学 · 物理学 2024-05-01 Shaily , J. K. Singh , Joao R. L. Santos , M. Zeyauddin

In this note, we investigate the stability of the dark energy model from time crystals proposed in [1]. We emphasize two ingredients, the coupling of the scalar field to gravity, and the fact that these time crystals are on an expanding FRW…

广义相对论与量子宇宙学 · 物理学 2025-08-27 Laura Mersini-Houghton

We investigate the viable exponential $f(R)$ gravity in the metric formalism with $f(R)=-\beta R_s (1-e^{-R/R_s})$. The latest sample of the Hubble parameter measurements with 23 data points is used to place bounds on this $f(R)$ model. A…

宇宙学与河外天体物理 · 物理学 2015-03-05 Yun Chen , Chao-Qiang Geng , Chung-Chi Lee , Ling-Wei Luo , Zong-Hong Zhu

Within the framework of modified teleparallel gravity, we reconstruct a f(T) model corresponding to the QCD ghost dark energy scenario. For a spatially flat FRW universe containing only the pressureless matter, we obtain the time evolution…

综合物理 · 物理学 2014-01-30 K. Karami , A. Abdolmaleki , S. Asadzadeh , Z. Safari

The evolution of linear cosmological perturbations in modified theories of gravity is investigated assuming the Palatini formalism. It has been discussed about the stability problem in this model based on the equivalence between f(R)…

广义相对论与量子宇宙学 · 物理学 2008-06-18 Seokcheon Lee

This article explores the cosmological scenario of the universe in the context of the $f(T)$ power law model, where $T$ represent the torsion scalar. To obtain the deterministic solution of the field equations we parametrized the effective…

广义相对论与量子宇宙学 · 物理学 2024-11-11 S. R. Bhoyar , Yash B. Ingole

Using a correspondence between the f(T)-gravity with the power-law entropy corrected version of the holographic dark energy model, we reconstruct the holographic f(T)-gravity model with power-law entropy correction. We fit the model…

广义相对论与量子宇宙学 · 物理学 2013-11-06 K. Karami , S. Asadzadeh , A. Abdolmaleki , Z. Safari

In this work, we investigate a cosmological scenario with a time-dependent cosmological constant $\Lambda$(t) within the spatially flat Friedmann-Lema\^itre-Robertson-Walker (FLRW) framework. Here we study a power-law $\Lambda(t)$CDM model…

广义相对论与量子宇宙学 · 物理学 2025-10-28 Archana Dixit , Manish Yadav , Anirudh Pradhan , M. S. Barak

We study cosmological evolution in a flat FLRW spacetime in the context of modified STEGR gravity or $f(Q)$, using an exponential two-parameter model which represents a smooth perturbative expansion around the $\Lambda$CDM model. The…

广义相对论与量子宇宙学 · 物理学 2025-04-15 Ivan R. Vasquez , A. Oliveros

We investigate some FLRW cosmological models in the context of Metric-Affine $F(R,Q)$ gravity, as proposed in [arXiv:1205.52666]. Here, $R$ and $Q$ are the curvature and nonmetricity scalars using non-special connections, respectively. We…

广义相对论与量子宇宙学 · 物理学 2024-08-16 Dinesh Chandra Maurya , K. Yesmakhanova , R. Myrzakulov , G. Nugmanova

In this paper, we consider an open system from the thermodynamic perspective for an adiabatic FRW universe model in which particle creation occurs within the system. In that case, the modified continuity equation is obtained and then we…

广义相对论与量子宇宙学 · 物理学 2022-12-14 S. Ganjizadeh , Alireza Amani , M. A. Ramzanpour
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