具有可变号相互作用项的广义查普瑞金宇宙学

发布时间：2018-06-14 07:00

本文选题：广义查普瑞金气体 + 可变号的相互作用项　；参考：《上海师范大学》2014年硕士论文

【摘要】：大量的天文学观测表明宇宙中存在着一种不能被直接观测且具有排斥力的能量,称为暗能量,它占宇宙总能量的73%左右。广义查普瑞金宇宙模型作为暗能量模型之一受到了人们的广泛讨论。但是这个模型和其他暗能量模型一样存在着宇宙巧合问题,因此引入了暗能量与暗物质的相互作用来缓解这个问题。本文讨论了具有可变号相互作用项的广义查普瑞金宇宙模型。第一章,主要介绍了现代宇宙学的观测基础和宇宙加速膨胀的模型,特别是被人们广泛研究的暗能量模型。文中也讨论了暗能量模型中存在的问题,尤其是宇宙巧合问题。为了缓解这个问题,理论物理学家在暗能量模型中引入了暗物质和暗能量的相互作用。第二章,阐述了查普瑞金宇宙模型、它的推广-广义查普瑞金宇宙模型以及具有相互作用项的广义查普瑞金宇宙模型。第三章,介绍了动力学系统的基础知识-自治系统和临界点,给出了线性系统临界点的分类方法和非线性系统临界点性质的判定。第四章,我们用动力学分析的方法,研究了具有可变号相互作用项的广义查普利瑞宇宙模型。找到了模型中存在的各种解并对这些解进行了完整分类。发现了一些稳定的吸引子解从而缓解了宇宙巧合问题,同时也发现了一些异宿轨线解。我们用数值方法研究了这个模型的宇宙演化,得到了一些不一样的结果,尤其是当相互作用项Q=3βqHρm时,在宇宙晚期,它的作用随着时间的演化越来越弱,直至无限趋向于零。所以当今暗物质不能被观测到,这个结果与最近的实验结果一致。第五章,总结所做的主要工作和展望未来的研究方向。
[Abstract]:A large number of astronomical observations show that there is a kind of energy which can not be observed directly and has repulsive force, called dark energy, which accounts for about 73% of the total energy of the universe. As one of the dark energy models, the generalized Chaplagine cosmic model has been widely discussed. But this model, like other dark energy models, has a cosmic coincidence problem, so the interaction between dark energy and dark matter is introduced to alleviate the problem. In this paper, the generalized Chaplagine cosmic model with variable sign interaction term is discussed. In the first chapter, the observational basis of modern cosmology and the model of accelerating expansion of the universe are introduced, especially the dark energy model, which has been widely studied. Problems in the dark energy model, especially the cosmic coincidence, are also discussed. To alleviate this problem, theoretical physicists introduce the interaction of dark matter and dark energy into the dark energy model. In the second chapter, the Chaplagine cosmic model, its generalization-generalized Chaplagine cosmic model and the generalized Chaplagine cosmic model with interaction term are described. In chapter 3, the basic knowledge of dynamical system-autonomous system and critical point are introduced, and the classification method of critical point of linear system and the judgment of critical point property of nonlinear system are given. In chapter 4, we study the generalized Chaprelli cosmic model with variable sign interaction term by means of dynamic analysis. The various solutions in the model are found and the complete classification of these solutions is given. Some stable attractor solutions are found to alleviate the cosmic coincidence problem and some heteroclinic orbital solutions are also found. We have studied the cosmic evolution of this model by numerical method, and obtained some different results, especially when the interaction term Q3 尾 qH 蟻 m, its action is weaker and weaker with time evolution in the late universe, until infinitely tends to zero. So dark matter can't be observed today, which is consistent with recent experimental results. The fifth chapter summarizes the main work done and looks forward to the future research direction.
【学位授予单位】：上海师范大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：P159

【共引文献】