摘要
依照目前的宇宙模型,宇宙之初是均匀而各向同性的。为了解释当前宇宙中观测到的各种星系结构,必须有某种机制导致均匀介质中出现结团以及结构演化。Jeans证明了一大团有质量的气体存在自引力不稳定性,它成为了宇宙结构演化的一般理论。在这个理论中需要早期宇宙各处存在密度涨落。另外,关于宇宙背景辐射的实验探测数据显示了背景光子温度存在微弱的各向异性,这些数据包含了有关基本宇宙参数,尤其是早期宇宙总能量密度和曲率的重要信息。通过对上述实验数据和理论的分析,从温度各向异性推算出了光子退耦时的密度相对涨落。
According to the cosmic model at present, the universe is symmetrical and isotropy at the begiuning. In order to ex- plain all kinds of galaxy＇s structures from the observation of today＇s universe, it has to be some mechanism which can induce conglomeration and structure evolvement in such symmetrical medium. Jeans proved an agglomerate gas is unstable by its self - gravitation and it has been a primeval theory about universe structure＇s evolvement. This theory needs a density fluctuation in ~tbe early universe. Otherwise, tiny inhomogeneities in the early universe left their imprint on the cosmic background radiation observations in the form of small ardsotropies in its temperature. These ardsotroples contain information about basic cosmological parameters, particularly the total energy density and curvature of the universe. By analyzing the experiment date and theory above, the anisotropy of temperature has been deduce to the density at the time of photon decoupling.
出处
《湖北师范学院学报（自然科学版）》
2013年第3期22-27,共6页
Journal of Hubei Normal University(Natural Science)
关键词
宇宙背景辐射
自引力不稳定性
各向异性
结构演化
暗物质
cosmic background radiation
self- gravitation instability
anisotropy
structure＇s evolvement
dark matter
