DBI暗物质暗能量统一模型的理论研究

发布时间：2018-04-24 09:39

本文选题：暗成分统一模型 + DBI理论　；参考：《辽宁师范大学》2014年硕士论文

【摘要】：目前，人们通过对Ia型超新星观测及WMAP、SDSS等精确观测数据的分析，表明宇宙正在加速膨胀。宇宙加速膨胀在物理学中是一个解释的焦点，对此人们提出了许多理论对标准宇宙学模型进行修正。此外，观测数据表明在宇宙中95%的能量密度是未知的暗成分。通常认为暗成分主要包含两部分：暗物质与暗能量。或者是认为这两种暗成分混合在一起，，被考虑成为一种全新未知暗流体。在本文中，我们从弦理论作用量出发，研究DBI(Dirac-Born-Infeld)作用量下一个暗物质暗能量统一模型。参考模型参数的数据限制结果，我们讨论在结构形成中一些宇宙学量的演化，如：密度反差和增长变量。最后，我们应用几何诊断的方法来区分DBI暗成分统一模型和最流行的宇宙学常数模型。通过给出几何量jerk参数的演化，可以看到暗成分统一模型与宇宙学常数模型的差别。研究表明，DBI统一模型可以作为解释宇宙加速膨胀的候选者。
[Abstract]:At present, the accurate observation data such as Ia supernova observation and WMAP-SDSS show that the universe is expanding rapidly. Accelerated expansion of the universe is a focus of explanation in physics, and many theories have been proposed to modify the standard cosmological model. In addition, observations show that 95% of the energy density in the universe is an unknown dark component. It is generally believed that the dark component consists of two parts: dark matter and dark energy. Or the two dark components are considered to be a new unknown dark fluid. In this paper, we study a unified model of dark matter dark energy under the action quantity of DBI Dirac-Born-Infeld. Referring to the data limitation results of the model parameters, we discuss the evolution of some cosmological variables in the formation of the structure, such as density contrast and growth variables. Finally, we use the geometric diagnosis method to distinguish the DBI dark component unified model from the most popular cosmological constant model. By giving the evolution of jerk parameters of geometric variables, we can see the difference between the unified dark component model and the cosmological constant model. It is shown that the unified model can be used as a candidate to explain the accelerating expansion of the universe.
【学位授予单位】：辽宁师范大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：P159;P145.9

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