论文标题
稳定性分析和互动粘性宇宙学的限制
Stability analysis and constraints on interacting viscous cosmology
论文作者
论文摘要
在这项工作中，我们通过考虑粘性的暗物质和深色能量和辐射的完美流体来研究空间平坦的宇宙的演变，包括暗物质和暗能量之间的相互作用项。在第一部分中，我们通过执行稳定性分析来分析宇宙的一般特性，然后使用哈勃参数的最新和宇宙学测量值来限制模型的自由参数。我们发现粘度系数与热力学第二定律所施加的条件之间的一致性。第二部分专门用于限制三种特定情况的相互作用粘性模型（IVM）的自由参数：粘性模型（VM），交互模型（IM）和完美的流体情况（一致性模型）。我们将减速参数报告为$ q_0 = -0.54^{+0.06} _ { - 0.05} $，$ -0.58^{+0.05} _ { - 0.04} $，$ -0.58^ $-0.63^{+0.02}_{-0.02}$, together with the jerk parameter as $j_0 = 0.87^{+0.06}_{-0.09}$, $0.94^{+0.04}_{-0.06}$, $0.91^{+0.06}_{-0.10}$, $1.0$ for IVM，VM，IM和LCDM分别在68 \％Cl中对应于不确定性。值得一提的是，在某些情况下，所有特定情况都与LCDM符合LCDM的吻合，从而产生更好的拟合，具有消除困扰标准宇宙学模型的一些问题。
In this work we study the evolution of a spatially flat Universe by considering a viscous dark matter and perfect fluids for dark energy and radiation, including an interaction term between dark matter and dark energy. In the first part, we analyse the general properties of the Universe by performing a stability analysis and then we constrain the free parameters of the model using the latest and cosmological-independent measurements of the Hubble parameter. We find consistency between the viscosity coefficient and the condition imposed by the second law of the Thermodynamics. The second part is dedicated to constrain the free parameter of the interacting viscous model (IVM) for three particular cases: the viscous model (VM), interacting model (IM), and the perfect fluid case (the concordance model). We report the deceleration parameter to be $q_0 = -0.54^{+0.06}_{-0.05}$, $-0.58^{+0.05}_{-0.04}$, $-0.58^{+0.05}_{-0.05}$, $-0.63^{+0.02}_{-0.02}$, together with the jerk parameter as $j_0 = 0.87^{+0.06}_{-0.09}$, $0.94^{+0.04}_{-0.06}$, $0.91^{+0.06}_{-0.10}$, $1.0$ for the IVM, VM, IM, and LCDM respectively, where the uncertainties correspond at 68\% CL. Worth mentioning that all the particular cases are in good agreement with LCDM, in some cases producing even better fits, with the advantage of eliminating some problems that afflicts the standard cosmological model.
