论文标题
$ f（t，b）$重力的宇宙学参数的定性稳定性分析
Qualitative Stability Analysis of Cosmological Parameters in $f(T,B)$ Gravity
论文作者
论文摘要
我们使用动力学系统分析分析了$ f（t，b）$重力的宇宙解决方案，其中$ t $是扭转标量，$ b $为边界术语标量。在我们的工作中，我们假设两个特定的宇宙学模型。对于第一个模型，我们考虑$ f（t，b）= f_ {0}（b^{k}+t^{m}）$，其中$ k $和$ m $是常数。对于第二型型号，我们考虑$ f（t，b）= f_ {0} t b $。我们通过引入新的无量纲变量来为每个模型生成一个微分方程的自主系统。为了求解该方程系统，我们使用动态系统分析。我们还研究了关键点及其本质，稳定条件及其宇宙扩展的行为。对于这两种型号，我们都会获得四个关键要点。该系统的相图进行了详细分析，并研究了它们的几何解释。在这两种模型中，我们都评估了密度参数，例如$ω_{r} $，$ω__{m} $，$ω_λ$和$ω________{eff} $和减速参数$（q）$并找到其合适的稳定性参数$λ$的范围。对于第一个模型，我们得到$ω_{eff} = -0.833，-0.166 $，对于第二型模型，我们得到$ω__{eff} = - \ frac {1} {1} {3} $。这表明两个模型都处于精髓阶段。此外，我们将EOS参数和减速参数的值与观察值进行比较。
We analyze the cosmological solutions of $f(T,B)$ gravity using dynamical system analysis where $T$ is the torsion scalar and $B$ be the boundary term scalar. In our work, we assume two specific cosmological models. For first model, we consider $ f(T,B)=f_{0}(B^{k}+T^{m})$, where $k$ and $m$ are constants. For second model, we consider $f(T,B)=f_{0}T B$. We generate an autonomous system of differential equations for each models by introducing new dimensionless variables. To solve this system of equations, we use dynamical system analysis. We also investigate the critical points and their natures, stability conditions and their behaviors of Universe expansion. For both models, we get four critical points. The phase plots of this system are analyzed in detail and study their geometrical interpretations also. In both model, we evaluated density parameters such as $Ω_{r}$, $Ω_{m}$, $Ω_Λ$ and $ω_{eff}$ and deceleration parameter $(q)$ and find their suitable range of the parameter $λ$ for stability. For first model, we get $ω_{eff}=-0.833,-0.166$ and for second model, we get $ω_{eff}=-\frac{1}{3}$. This shows that both the models are in quintessence phase. Further, we compare the values of EoS parameter and deceleration parameter with the observational values.
