自生宇宙模型的相关研究

自生宇宙模型假定爱因斯坦静态作为宇宙演化的初始态，从而为解决标准宇宙学模型中的奇点问题提供了一种可能的途径。因此，稳定的爱因斯坦静态宇宙对自生模型至关重要。本项目拟系统地对自生宇宙模型展开相关研究。首先，将研究一些修改引力理论中是否存在稳定的爱因斯坦静态解；其次，将研究从静态到暴胀过程对宇宙密度扰动功率谱的修正，探讨其是否可以解释CMB温度功率谱的大尺度压低和在多极矩l约为20处的下降；此外，分析从静态到缓慢膨胀的演化过程，探讨其对密度功率谱的影响。最后，利用CMB观测数据对理论模型进行限制，得到观测比较支持的理论模型。本项目的研究将可能帮助我们得到宇宙起源的相关信息。

The emergent scenario assumes that our universe originates from the Einstein static state, and it provides a possible way to resolve the big bang singularity problem of standard cosmological model. Thus, a stable Einstein static sate is crucial for the emergent scenario. In this project, we will focus on some investigations on the emergent model. Firstly, the stability conditions of the Einstein static universe in some modified gravitational theories will be studied. Then, we will analyze the corrections on inflationary power spectrum of density perturbation from static state to inflation and discuss whether it can be used to explain the large-scale suppression and the dip at multipole l ∼ 20 obsereved in the CMB. Following, the effect of slow expansion on power spectrum of density perturbation will be investigated. Finally, using the observational data of CMB to restrict theoretical models, theoretical models supported by observations are obtained. The results of this project can help us obtain information about the origin of the universe.