论文标题
在粘度存在下的$λ$ CDM的限制和宇宙学
Constraints and cosmography of $Λ$CDM in presence of viscosity
论文作者
论文摘要
在这项工作中，我们研究了宇宙的两种情况，这些场景是由传统的暗能量之后的完美液体和粘性的液体作为暗物质的。从这个意义上讲，我们探讨了Eckart形式主义中粘度的最简单情况，即常数，然后是红移的多项式函数。我们通过基于马尔可夫链蒙特卡洛方法进行贝叶斯分析，并使用哈勃参数（OHD），类型IA Supernovae（SNIA）和强透镜系统来限制模型参数的相空间。前两个样本覆盖该地区$ 0.01 <z <2.36 $。基于AIC，我们发现这些粘性模型同样支持lambda-cold暗物质（LCDM），同时考虑到OHD或SNIA。另一方面，我们重建了cosmographic参数（$ q，j，s，l $），并在最高$3σ$ cl内找到良好的LCDM。此外，我们发现，磁化参数和加速度 - 偏移过渡与与粘度系数相关的参数明智，使粘度成为修改它们的有趣物理机制。
In this work, we study two scenarios of the Universe filled by a perfect fluid following the traditional dark energy and a viscous fluid as dark matter. In this sense, we explore the simplest case for the viscosity in the Eckart formalism, a constant, and then, a polynomial function of the redshift. We constrain the phase-space of the model parameters by performing a Bayesian analysis based on Markov Chain Monte Carlo method and using the latest data of the Hubble parameter (OHD), Type Ia Supernovae (SNIa) and Strong Lensing Systems. The first two samples cover the region $0.01<z<2.36$. Based on AIC, we find equally support of these viscous models over Lambda-Cold Dark Matter (LCDM) taking into account OHD or SNIa. On the other hand, we reconstruct the cosmographic parameters ($q,j,s,l$) and find good agreement to LCDM within up to $3σ$ CL. Additionally, we find that the cosmographic parameters and the acceleration-deceleration transition are sensible to the parameters related to the viscosity coefficient, making of the viscosity an interesting physical mechanism to modified them.
