暗能量模型及其分析与比较
发布时间：2019-06-22 18:09
【摘要】：天文学在上个世纪取得了极大的进展。从爱因斯坦提出广义相对论并将其运用到宇宙学,到哈勃发现宇宙膨胀,加莫夫提出宇宙大爆炸理论,威尔逊、彭齐亚斯发现宇宙微波背景辐射,再到1998年两个超新星小组发现宇宙加速膨胀,占宇宙总能量73%的暗能量旋即成为宇宙学研究的热点与重点。本文从宇宙加速膨胀、暗能量以及Ia型超新星等背景知识出发,主要介绍了宇宙学常数模型、全息暗能量模型以及Quintessence、Phantom、Quintom、Tachyon、Chaplygin Gas等几类较为经典的动力学暗能量模型,定性地分析了各类模型的优点与缺点。宇宙学常数模型虽然形式上简单明了,并且与观测事实符合得很好,但是白璧微瑕,它仍然存在精细调节问题和巧合性问题两大难题。Quintessence暗能量模型的状态方程不像宇宙学常数模型那样是一个常数,它在(-1,+1)区间内是可变的；并且该模型不存在巧合性问题。Phantom暗能量模型与Quintessence相似,但是它解决了暗能量状态方程有可能穿越-1的问题,其不足在于可以导致宇宙大撕裂。Quintom暗能量模型则是Quintessence和Phantom的综合,它同时具备两类模型的一些性质。全息暗能量是基于量子力学的全息原理提出的一种暗能量模型,其状态方程只有一个参数c,可以在-1附近变化。 由于当前暗能量模型各式各样,我们迫切需要找到一种方法对这些模型进行分析与甄别。Statefinder就是这样一种方法。Statefinder的基本思路是通过引进Statefinder参数对{r,s㘎,比较暗能量模型在s-r平面上与固定点{0,1}亦即ΔCDM模型的距离。本文通过该方法主要分析与比较了Chaplygin Gas暗能量模型和全息暗能量模型,着重研究了修正Chaplygin Gas暗能量模型以及一般形式下带尘埃的Chaplygin Gas暗能量模型的s-r关系,并给出了上述几类暗能量模型在s-r平面上的演化行为。
[Abstract]:Astronomy has made great progress in the last century. From Einstein's general relativity and its application to cosmology, to Hubble's discovery of cosmic expansion, Gamov's theory of the Big Bang, Wilson and Penzias's discovery of cosmic microwave background radiation, and then in 1998, two supernova groups found that the universe expanded rapidly, accounting for 73% of the total energy of the universe. Based on the background knowledge of cosmic accelerated expansion, dark energy and IA type supernova, this paper mainly introduces some classical dynamic dark energy models, such as cosmological constant model, holographic dark energy model and Quintessence,Phantom,Quintom,Tachyon,Chaplygin Gas, and qualitatively analyzes the advantages and disadvantages of these models. Although the cosmological constant model is simple and clear in form and in good agreement with the observed facts, it still has two problems: fine adjustment problem and coincidence problem. The equation of state of the Quintessence dark energy model is not as constant as the cosmological constant model, and it is variable in the (- 1, 1) range. There is no coincidence problem in this model. Phantom dark energy model is similar to Quintessence, but it solves the problem that dark energy equation of state may cross-1, which can lead to large tear of the universe. Quintom dark energy model is a synthesis of Quintessence and Phantom, and it has some properties of two kinds of models at the same time. Holographic dark energy is a dark energy model based on the holographic principle of quantum mechanics. Its equation of state has only one parameter c, which can be changed near-1. Because of the variety of dark energy models, we urgently need to find a method to analyze and identify these models. StateFinder is such a method. The basic idea of StateFinder is to compare the distance between the dark energy model and the fixed point {0, 1}, that is, 螖 CDM model, by introducing the Statefinder parameter pair {r, s 鈮，
本文编号：2504834
[Abstract]:Astronomy has made great progress in the last century. From Einstein's general relativity and its application to cosmology, to Hubble's discovery of cosmic expansion, Gamov's theory of the Big Bang, Wilson and Penzias's discovery of cosmic microwave background radiation, and then in 1998, two supernova groups found that the universe expanded rapidly, accounting for 73% of the total energy of the universe. Based on the background knowledge of cosmic accelerated expansion, dark energy and IA type supernova, this paper mainly introduces some classical dynamic dark energy models, such as cosmological constant model, holographic dark energy model and Quintessence,Phantom,Quintom,Tachyon,Chaplygin Gas, and qualitatively analyzes the advantages and disadvantages of these models. Although the cosmological constant model is simple and clear in form and in good agreement with the observed facts, it still has two problems: fine adjustment problem and coincidence problem. The equation of state of the Quintessence dark energy model is not as constant as the cosmological constant model, and it is variable in the (- 1, 1) range. There is no coincidence problem in this model. Phantom dark energy model is similar to Quintessence, but it solves the problem that dark energy equation of state may cross-1, which can lead to large tear of the universe. Quintom dark energy model is a synthesis of Quintessence and Phantom, and it has some properties of two kinds of models at the same time. Holographic dark energy is a dark energy model based on the holographic principle of quantum mechanics. Its equation of state has only one parameter c, which can be changed near-1. Because of the variety of dark energy models, we urgently need to find a method to analyze and identify these models. StateFinder is such a method. The basic idea of StateFinder is to compare the distance between the dark energy model and the fixed point {0, 1}, that is, 螖 CDM model, by introducing the Statefinder parameter pair {r, s 鈮，
本文编号：2504834
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