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相关论文: Late time cosmological approach in mimetic $f(R,T)…

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We study the late time cosmological evolution of $f(R)$ theories of modified gravity, with the matter content of the universe being that of collisional self interacting matter. We assume that the universe is described by a flat…

广义相对论与量子宇宙学 · 物理学 2015-06-22 V. K. Oikonomou , N. Karagiannakis

The problem of cosmic acceleration and dark energy is one of the mysteries presently posed in the scientific society that general relativity has not been able to solve. In this work, we have considered alternative models to explain this…

广义相对论与量子宇宙学 · 物理学 2022-12-01 M. Koussour , N. Myrzakulov , S. H. Shekh , M. Bennai

We demonstrate how to describe in an unified way early and late-time acceleration in the context of mimetic $F(R)$ gravity. As we show, an exponential $F(R)$ gravity model has appealing features, with regard to unification, and we perform…

广义相对论与量子宇宙学 · 物理学 2016-10-06 V. K. Oikonomou

In this study, we explored late-time cosmology within an extended class of theories based on $f(Q, L_m)$ gravity. This theory generalizes $f(Q)$ gravity by incorporating a non-minimal coupling between the non-metricity $Q$ and the matter…

宇宙学与河外天体物理 · 物理学 2024-10-07 Kairat Myrzakulov , M. Koussour , O. Donmez , A. Cilli , E. Güdekli , 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

The article communicates an alternative route to suffice the late-time acceleration considering a bulk viscous fluid with viscosity coefficient $\zeta =\zeta _{0}+ \zeta _{1} H + \zeta _{2} H^{2}$, where $\zeta _{0}, \zeta _{1}, \zeta _{2}$…

广义相对论与量子宇宙学 · 物理学 2020-07-20 Simran Arora , Snehasish Bhattacharjee , P. K. Sahoo

In this work, we study the late-time cosmological solutions of f(R,T)=g(R)+h(-T) models assuming that the conservation of the energy-momentum tensor (EMT) is violated. We perform our analysis through constructing an autonomous dynamical…

广义相对论与量子宇宙学 · 物理学 2017-08-07 Hamid Shabani , Amir Hadi ziaie

This thesis investigates late-time cosmic acceleration using modified gravity theories with a focus on $f(Q)$ gravity, as an alternative to the $\Lambda$CDM model. The standard cosmological model attributes the acceleration to a…

广义相对论与量子宇宙学 · 物理学 2025-12-18 S. A. Narawade

This thesis focuses on late-time cosmic acceleration within modified theories of gravity, using various observational data sets and statistical analysis. The Universe is assumed to be spatially homogeneous and isotropic and is described by…

广义相对论与量子宇宙学 · 物理学 2025-03-05 Santosh V. Lohakare

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

In this paper we propose and extensively study mimetic $f({\cal G})$ modified gravity models, with various scenarios of cosmological evolution, with or without extra matter fluids. The easiest formulation is based on the use of Lagrange…

广义相对论与量子宇宙学 · 物理学 2015-09-23 Artyom V. Astashenok , Sergei D. Odintsov , V. K. Oikonomou

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

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…

广义相对论与量子宇宙学 · 物理学 2016-02-17 S. D. Odintsov , V. K. Oikonomou

We review the accelerating (mainly, dark energy) cosmologies in modified gravity. Special attention is paid to cosmologies leading to finite-time future singularities in $F(R)$, $F(G)$ and $\mathcal{F}(R,G)$ modified gravities. The removal…

广义相对论与量子宇宙学 · 物理学 2013-02-21 Kazuharu Bamba , Shin'ichi Nojiri , Sergei D. Odintsov

In this paper, we have presented the cosmological model of the Universe that represents late time cosmic acceleration in torsion based gravitational theory, the $f(T)$ gravity. A well motivated parametrization for the Hubble parameter has…

广义相对论与量子宇宙学 · 物理学 2025-11-04 Suraj Kumar Behera , Pratik P. Ray , B. Mishra

The paper presents late time cosmology in $f(Q,T)$ gravity where the dark energy is purely geometric in nature. We start by employing a well motivated $f(Q,T)$ gravity model, $f(Q,T)=mQ^{n}+bT$ where $m,n$ and $b$ are model parameters.…

广义相对论与量子宇宙学 · 物理学 2020-07-06 Simran Arora , S. K. J. Pacif , Snehasish Bhattacharjee , P. K. Sahoo

In this research paper, we explore a well-motivated parametrization of the time-dependent deceleration parameter, characterized by a cubic form, within the context of late time cosmic acceleration. The current analysis is based on the…

广义相对论与量子宇宙学 · 物理学 2023-12-19 Madhur Khurana , Himanshu Chaudhary , Saadia Mumtaz , S. K. J. Pacif , G. Mustafa

This thesis investigates the characteristics of modified teleparallel gravity models that incorporate a scalar field and a trace of the energy-momentum tensor, with particular attention to their cosmological effects, especially regarding…

广义相对论与量子宇宙学 · 物理学 2025-10-06 L K Duchaniya

In this article, we explore the comprehensive narrative of cosmic evolution within a cosmological framework by utilizing a novel form of gravity known as generalized symmetric teleparallel gravity, denoted as $f(Q,T)$ gravity. Here, $Q$…

综合物理 · 物理学 2024-09-10 Surajit Das , Sanjay Mandal

In this work, we present a method for numerically solving the Friedmann equations of modified $f(\mathcal{G})$ gravity in the presence of pressureless matter. This method enables us to predict the redshift behaviour of the Hubble expansion…

广义相对论与量子宇宙学 · 物理学 2024-11-08 Santosh V. Lohakare , Soumyadip Niyogi , B. Mishra
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