arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2402.01780gr-qcastro-ph.CO
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$f(R,T)$引力中含二次曲率项的晚期幻影特性

Late time phantom characteristic of the model in $f(R,T)$ gravity with quadratic curvature term

Shaily, Akanksha Singh, J. K. Singh, Saibal Ray

AI总结:

提出含$R^m$和$T^n$高阶项的$f(R,T)$引力模型,利用OHD和Pantheon数据约束,显示早期减速晚期加速,可解释暗能量。

摘要:

我们在$f(R,T)$型修正引力理论框架内提出了一种新颖的宇宙学模型,该模型包含与里奇标量($R$)的高阶项以及能量-动量张量的迹($T$)的非最小耦合。因此,我们精心选择的$f(R,T)$表达式为$ R + R^m + 2 λT^n$,其中$λ$、$m$和$n$是任意常数。采用恒定的加加速度参数($j$),我们推导出了减速参数($q$)和哈勃参数($H$)作为红移$z$的函数的表达式。我们利用马尔可夫链蒙特卡洛(MCMC)分析,用最新的观测哈勃数据集(OHD)、$Pantheon$以及$Pantheon$+OHD数据集对模型进行了约束。我们的模型显示出早期减速随后晚期加速的演化,转变发生在红移范围$1.10 \leq z_{tr} \leq 1.15$内。我们的研究结果表明,这种$f(R,T)$引力理论的高阶模型能够有效地提供一个暗能量模型,以解释当前宇宙加速膨胀的现状。

英文摘要:

We propose a novel cosmological framework within the $f(R,T)$ type modified gravity theory, incorporating a non-minimally coupled with the higher order of the Ricci scalar ($R$) as well as the trace of the energy-momentum tensor ($T$). Therefore, our well-motivated chosen $f(R,T)$ expression is $ R + R^m + 2 λT^n$, where $λ$, $m$, and $n$ are arbitrary constants. Taking a constant jerk parameter ($j$), we derive expressions for the deceleration parameter ($q$) and the Hubble parameter ($H$) as functions of the redshift $z$. We constrained our model with the recent Observational Hubble Dataset (OHD), $Pantheon$, and $ Pantheon $ + OHD datasets by using the analysis of Markov Chain Monte Carlo (MCMC). Our model shows early deceleration followed by late-time acceleration, with the transition occurring in the redshift range $1.10 \leq z_{tr} \leq 1.15$. Our findings suggest that this higher-order model of $f(R,T)$ gravity theory can efficiently provide a dark energy model for addressing the current scenario of cosmic acceleration.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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