Gravity and Structure of Universe

关于宇宙的结构，有两类问题，即“全局”问题和“局部”问题。全局结构意味着超越当前视界的整体结构，这个问题与宇宙的量子创造和之后的暴胀有关。局部结构包括密度摄动的产生问题和暗物质和重子物质现有密度结构的识别问题。另一方面，弦论等包括引力在内的统一理论的试验表明，广义相对论存在修改，这可能会影响宇宙创造的过程。考虑到这些情况，这个研究项目的组织是为了研究结构的这两个方面与重力理论的关系。本项目研究的课题包括：量子宇宙学：通过引入宇宙时间变量，量子黑洞，类似薛定谔的惠勒-德维特方程公式。具有R^2的拉格朗日：混沌暴胀的新效应，黑洞结构，非线性引力波宇宙模型：高维mixmaster模型，Nariai度规和Kantowski度规暴胀：封闭模型的混沌暴胀，暴胀阶段重子数的产生，曲率波动的产生以及再加热阶段粒子和反粒子的分离。暗物质与核合成；轻子数与He、Li丰度；衰变粒子对宇宙背景的光谱修饰；结构形成：规范不变理论中等温摄动的增长；宇宙弦与螺旋星系旋转速度的星系形成；IRAS数据与包含衰变粒子和宇宙常数的宇宙模型的比较。

As to the structure of universe, there are two kinds of problem, that is, "global" and "local". Global structure implies an overall structure beyond the present horizon ahd this problem is related to a scenario of quantum creation of universe and the Inflation afte that. Local structure comprises problems on generation of density perturbation and recognition of the present density structure for dark matter as well as for baryon matter. On the other hand, trial of the unified theory including gravity such as the string theory has indicated a modifiction of the general relativity, which might affect the process near the creation of universe. Considering these situations, this research project was organised in order to study these two aspects of the structure in relation to the theory of gravity.The subjects stdied in this project include the followings. Quantum Cosmology : Schrodinger like formulation of the Wheeler-DeWitt equation through an introduction of the cosmic-time variables, quantum black hole. Lagrangian with R^2 : New effects for chaotic inflation, black hole structure, nonlinear gravitational wave Universe models : higher dimensional mixmaster model, Nariai metric and Kantowski metric Inflation : chaotic inflation of closed models, baryon number generation during the inflation stage, generation of curveture fluctuation and separation of particle and antiparticles at the reheating phase. Dark matter and nucleosynthesis : lepton number and He, Li abundance, spectrum modification of the cosmic background by decaying particles Structure formation : growth of isothermal perturbation in gauge-invariant theory, galaxy formation by cosmic string and rotation velocity of spiral galaxy, comparison of IRAS data with universe models containing decaying particles and cosmological constant.