标题： 粘性宇宙流体与大尺度结构 显示英文标题

标题： Viscous cosmological fluids and large-scale structure

摘要： 本文研究了一种粘性流体力学宇宙模型，当满足某些条件时，该模型能够模拟出与$\Lambda$CDM 模型相似的结果。推导了描述多流体系统中粘性相互作用流体演化的背景方程。利用超新星 Ia 型数据，应用马尔科夫链蒙特卡洛（MCMC）方法约束最佳拟合的宇宙学参数。此外，采用$1+3$协变形式的方法，在尘埃物质主导的框架下研究了线性的宇宙扰动。从扰动结果可以明显看出，该模型预测晚期宇宙中大尺度结构的束缚结构会瓦解。 显示英文摘要

摘要： In this paper, we study the viscous fluid cosmological model that when certain conditions are invoked mimics the $\Lambda$CDM model. The background equations governing the evolution of viscous interacting fluids in a multifluid system are derived. The Markov Chain Monte Carlo (MCMC) simulation is applied to constrain the best-fit cosmological parameters with Supernova Type 1a data. In addition, linear cosmological perturbations are investigated in a dust-matter-dominated frame using a $1+3$ covariant formalism approach. It is evident from the perturbation results obtained that the model predicts the disintegration of bound structures of large-scale structures in the late-time universe.