中文
相关论文

相关论文: Resolving FLRW cosmology through effective equatio…

200 篇论文

This paper explores models of the FLRW universe that incorporate a time-varying cosmological term $\Lambda(t)$. Specifically, we assume a power-law form for the cosmological term as a function of the scale factor: $\Lambda(t)=\Lambda_{0}…

宇宙学与河外天体物理 · 物理学 2024-05-14 M. Koussour , N. Myrzakulov , J. Rayimbaev

We study the evolution of the cosmological parameters, namely, the deceleration parameter $q(z)$ and the parameter of effective equation of state in a universe contains, besides the ordinary matter and dark energy, a self-interacting…

广义相对论与量子宇宙学 · 物理学 2015-11-04 E. H. Baffou , M. J. S. Houndjo , M. E. Rodrigues , A. V. Kpadonou , J. Tossa

This article deals with a cosmological scenario in $ f(R,T) $ gravity for a flat FLRW model of the universe. We consider the $ f(R,T) $ function as $ f(R)+f(T) $ which starts with a quadratic correction of the geometric term $ f(R) $ having…

广义相对论与量子宇宙学 · 物理学 2022-05-03 Ritika Nagpal , J. K. Singh , A. Beesham , Hamid Shabani

In the context of f(R, T) gravity theory for the flat Friedmann Lemaitre Robertson Walker (FLRW) model, the accelerating expansion of the universe is investigated using a specific form of the emergent Hubble parameter. Datasets from H(z),…

广义相对论与量子宇宙学 · 物理学 2025-01-16 N. Myrzakulov , S. H. Shekh , Anirudh Pradhan , Archana Dixit

In this letter, we investigate the cosmic expansion scenario of the universe in the framework of $f(R,L_m)$ gravity theory. We consider a non-linear $f(R,L_m)$ model, specifically, $f(R,L_m)=\frac{R}{2}+L_m^n + \beta$, where $n$ and $\beta$…

广义相对论与量子宇宙学 · 物理学 2023-11-02 Lakhan V. Jaybhaye , Raja Solanki , Sanjay Mandal , P. K. Sahoo

In this article, we study the expanding nature of universe in the contest of $f(R,L_m)$ gravity theory, here $ R $ represents the Ricci scalar and $ L_m $ is the matter Lagrangian density. With a specific form of $ f(R,L_m) $, we obtain the…

广义相对论与量子宇宙学 · 物理学 2023-06-28 J. K. Singh , Shaily , Ratbay Myrzakulov , Harshna Balhara

In this paper, we examine the universe's expansion in $ f(R, L_{m}) $ gravity for a particular form of $ f(R, L_{m})=\frac{R}{2}+L_{m}^{n}$. The field equations for flat FLRW metric with matter Lagrangian $ L_{m}=\rho$ are derive. Hubble…

广义相对论与量子宇宙学 · 物理学 2025-02-12 Romanshu Garg , G. P. Singh , Ashwini R Lalke , Saibal Ray

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

In this paper, we have explored the field equations of f(T, B) gravity as an extension of teleparallel gravity in an isotropic and homogeneous space time. In the basic formalism developed, the dynamical parameters are derived by…

广义相对论与量子宇宙学 · 物理学 2024-09-27 S. A. Kadam , Jackson Levi Said , B. Mishra

This study systematically investigates the cosmological dynamics of two well-motivated functional forms in $f(T,B)$ gravity within a flat Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) universe. Here $T$ denotes the torsion scalar and $B$…

广义相对论与量子宇宙学 · 物理学 2026-02-16 Jianwen Liu , Fabao Gao , Aqeela Razzaq

In this paper, we consider a comprehensive investigation of the cosmological model described by $f(R,T) = R + 2\lambda T$ (where $\lambda$ represents a free parameter) in light of the most recent observational data. By constraining the…

宇宙学与河外天体物理 · 物理学 2023-09-29 N. Myrzakulov , M. Koussour , Alnadhief H. A. Alfedeel , E. I. Hassan

We investigate cosmological solutions of f(R,T) modified theories of gravity for perfect fluid in spatially FLRW metric through phase space analysis, where R is Ricci scalar and T denotes the trace of energy-momentum tensor of matter…

广义相对论与量子宇宙学 · 物理学 2017-05-23 Hamid Shabani , Mehrdad Farhoudi

An exact cosmological solution of Einstein field equations (EFEs) is derived for a dynamical vacuum energy in $f(R,T)$ gravity for Friedmann-Lemaitre-Robertson-Walker (FLRW) space-time. A parametrization of the Hubble parameter is used to…

综合物理 · 物理学 2018-11-22 Ritika Nagpal , S. K. J. Pacif , J. K. Singh , Kazuharu Bamba , A. Beesham

In this paper, a general FRW cosmological model has been constructed in $f(R,T)$ gravity reconstruction with variable cosmological constant. A number of solutions to the field equations has been generated by utilizing a form for the Hubble…

广义相对论与量子宇宙学 · 物理学 2018-10-17 Nasr Ahmed , Sultan Z. Alamri

We investigate the cosmological evolution in a new modified teleparallel theory, called $f(T,B)$ gravity, which is formulated by connecting both $f(T)$ and $f(R)$ theories with a boundary term $B$. Here, $T$ is the torsion scalar in…

综合物理 · 物理学 2018-11-14 M. Zubair , Saira Waheed , M. Atif Fayyaz , Iftikhar Ahmad

The $f(T)$ gravity is one of the extensions of teleparallel equivalent of general relativity, in which more general functions of the torsion scalar $T$ can be described. With the proposed functional form of $f(T) = \alpha T - \beta u^{-n} +…

广义相对论与量子宇宙学 · 物理学 2026-04-14 Suraj Kumar Behera , S. A. Kadam , Pratik P. Ray , B. Mishra

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

New high-precision observations are now possible to constrain different gravity theories. To examine the accelerated expansion of the Universe, we used the newly proposed $f(Q,T)$ gravity, where $Q$ is the non-metricity, and $T$ is the…

广义相对论与量子宇宙学 · 物理学 2021-06-30 Simran Arora , Abhishek Parida , P. K. Sahoo

In this paper, a general entropy-corrected FRW cosmological model has been presented in which a deceleration-to-acceleration transition occurs according to recent observations. We found that the case for the flat universe ($k=0$), supported…

广义相对论与量子宇宙学 · 物理学 2019-10-23 Nasr Ahmed , Sultan Z. Alamri

This work examines the cosmological implications of two functional forms of $f(R,T) = R + \alpha T^n$ gravity: for two different value of $n $ where $n=1$ and $n\neq 1$, and $\alpha$ and $n$ are free parameters. The modified Friedmann…

宇宙学与河外天体物理 · 物理学 2026-02-24 Mustapha Lamaaoune
‹ 上一页 1 2 3 10 下一页 ›