论文标题
考虑到运行真空模型，在循环宇宙中统一转向弹跳宇宙学
Unifying turnaround-bounce cosmology in a cyclic universe considering a running vacuum model
论文作者
论文摘要
在许多可以描述弹跳宇宙学的模型中，一个弹跳场景因跑步的暗能量（RVM-DE）而变形的物质情景感兴趣。在这项研究中，我表明一类RVM-CDM（冷暗物质）模型还可以描述一个周期性的宇宙学，其中宇宙经历了扩展到收缩阶段的周期，反之亦然。为此，在我们先前的工作之后，我考虑了弹跳宇宙学中最成功的RVM-CDM模型之一，$ρ_x= n_0 +n_0 +n_2 +n_2 +n_4 h^4 $，功率频谱指数获得红色倾斜度，光谱指数的运行可能会通过选择适当的值来提供paramet的均值（$ n_2 $ n_2）。宇宙学观察。值得一提的是，大多数弹跳模型不会产生这种负值。但是，本文的主要目的是在周转阶段研究RVM-CDM模型。在幻象扩展的宇宙中，远离反弹，在突然发生的大裂口发生之前，对周转条件进行了研究。通过分析围绕周转的哈勃参数，状态参数方程和减速参数，我们表明，通过选择适当的参数值，可以在\ textbf {互动}情况下进行\ textbf {互动}情况的扩展后发生成功的周转。获得交互参数的最小值，并找到其他模型参数之间的任何关系。最后，研究了每个参数对周转的影响，我们看到，对于较大的交互参数值，从加速到减速扩展的过渡时间可能更早地发生。同样，在几个图中，研究了第二项在包括$ h^2 $在内的第二项的效果，我们看到，通过增加其系数（$ n_2 $），过渡点会导致较低的值。
Among many models which can describe the bouncing cosmology, A matter bounce scenario that is deformed by a running vacuum model of dark energy (RVM-DE) has been interested. In this research, I show that a class of RVM-CDM (cold dark matter) model can also describe a cyclical cosmology in which the universe undergoes cycles of expansion to the contraction phase and vice versa. To this end, following our previous work, I consider one of the most successful class of RVM-CDM model in bouncing cosmology, $ρ_x=n_0+n_2 H^2 +n_4 H^4$, in which the power spectral index gets a red tilt and the running of the spectral index may give a negative value by choosing the appropriate value of parameters ($n_0,~n_2,~n_4$), which is consistent with the cosmological observations. It is worthwhile to mention that most matter bounce models do not produce this negative value. However, the main purpose of this article is to investigate the RVM-CDM model in the turnaround phase. Far from the bounce in a phantom expanding universe, the turnaround conditions are investigated before the occurrence of a sudden big rip. By analyzing the Hubble parameter, equation of state parameter, and deceleration parameter around the turnaround, we show that a successful turnaround may occur after an expansion in an \textbf{interacting} case of RVM-CDM by choosing the appropriate value of parameters. A minimum value for the interaction parameter is obtained and also finds any relation between other model parameters. Finally, the effect of each parameter on a turnaround is studied, and we see that the transition time from accelerating to decelerating expansion can occur earlier for larger values of interaction parameters. Also, in several graphs, the effect of the second term in DE density, including $H^2$, is studied, and we see that by increasing its coefficient, $n_2$, the transition point leads to lower values.
