文档介绍：暴涨宇宙论李淼中国科学院理论物理研究所Cosmic InflationMiao LiInstitute of Theoretical Physics, Academia SinicaThe standard cosmological model, the big bang model, has been met with numerous esses, including:(1) Prediction of cosmic microwave background.(2) Prediction of the abundance of light elements such helium and deuterium.(3) Of course, explanation of Hubble’s law.……Part I InflationStill, the standard big bang model does notexplain everything we observe. For example, how the structure we see in the sky formed? Why the universe is as old as about 14 billion years? need a theory of initial conditions to answer questions that the big bang model does notanswer. Inflation was invented to partially answer these questions. Traditionally, three problems associated to the initial conditions are most often quoted:(a)The first problem is called the horizon problem.(b)The second problem is the flatness problem.(c) Unwanted to many cosmologists, the most practical use of inflation scenario is the generation of primordial perturbations, it is these three “philosophical” problems that motivated Alan Guth to invent inflation in now describe the three problems before presenting the solution offered by inflation.(a)The horizon with the Friedmann-Robert-Walker metricThe most distant places in early universe at time t we can observe today is given byFor a matter-dominated universe, if , thenHowever, the particle horizon at that time, againfor a matter-dominated universe, isThe ratio of the two is When the light last scattered, z~1000, the above ratiois already quite small. The smaller the t, the smallerthe ratio, this is the horizon problem: why the universe is homogeneous in a much larger pared to the particle horizon?(b) The flatness a universe with a spatial curvature, characterized by a number , one of the Friedmann equations readswhere H is the Hubble “constant”