论文标题
$ f（r，l_m）$重力的受限宇宙学模型
A constrained cosmological model in $f(R,L_m)$ gravity
论文作者
论文摘要
在本文中，我们研究了$ f（r，l_m）$重力理论的宇宙的扩展性质，这里$ r $代表RICCI标量，而$ l_m $是Lagrangian密度。以$ f（r，l_m）$的特定形式，我们获得了Flat Flrw度量的字段方程。我们以哈勃参数来参数化减速参数，从这里我们找到四个免费参数，它们是约束，并通过使用$ h（z）$，$ pantheon $及其联合数据集来估算。此外，我们研究了减速参数的演变，该参数描述了从减速到宇宙加速阶段的过渡。能量密度，压力和EOS参数的演化行为表明，当前模型是加速的典型暗能量模型。为了将我们的模型与$λ$ CDM模型进行比较，我们使用了一些诊断技术。因此，我们发现我们的模型在$ f（r，l_m）$重力中支持最近的标准观察性研究，并描述了延迟时间宇宙加速度。
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 field equations for flat FLRW metric. We parametrize the deceleration parameter in terms of the Hubble parameter and from here we find four free parameters, which are constraints and estimated by using $H(z)$, $Pantheon$, and their joint data sets. Further, we investigate the evolution of the deceleration parameter which depicts a transition from the deceleration to acceleration phases of the universe. The evolution behaviour of energy density, pressure, and EoS parameters shows that the present model is an accelerated quintessence dark energy model. To compare our model with the $ Λ$CDM model we use some of the diagnostic techniques. Thus, we find that our model in $ f(R,L_m) $ gravity supports the recent standard observational studies and delineates the late-time cosmic acceleration.
