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介绍了有关宇宙微波背景辐射(CBR)观测和理论研究的最新进展。叙述了基于COBE卫星的观测宇宙学,包括对背景辐射谱,各向异性的观测结果及其理论意义;并系统介绍了CBR各向异性形成的种种机制;展望了下一代宇宙微波背景探测器(MAP和PLANCK)的科学目标和主要技术参数。 相似文献
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我学校为了帮助学生更多地了解天文知识,建立正确的宇宙观,在学生科普教育中,比较早的开展了天文普及活动。从八十年代初到现在,学校没有间断过天文选修课的设立。在初中、高中都开设了天文选修,高中的学生还自己成立了天文社团。这样课内课外相结合,为喜爱天文的学生提供了个性发展的条件。 相似文献
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T.Kiang 《中国天文和天体物理学报》2003,3(2):95-104
A new way of probing the harge-scale structure of the universe is proposed.Space is partitioned into cells the shape of rhombic dodecahedron.The cells are labelled “filled“ or “empty“ according as they contain galaxies or not ,the cell size is so chosen as to have narly equal numbers of filled and empty cells for the given galaxy sample.Two observables on each cell are definable:the number of ist like neighbors,n1,and a two-suffixed topological type τ,the suffixes being the numbers of its like and unlike neighbor-groups.The frequency distributions of n1 and τ in the observed set of filled(empty)cells are then considered as indicators of the morphology of the set,The method is applied to the CfA catalogue of galaxies as an illustration.Despite its limited size,the data offers evidence 1) that the empty cells are more stongly clustered than the filled cells,and 2) theat the filled cells,but not the empty cells,have a tendency to occur in sheets,Further directions of development both in theory and application are indicated. 相似文献
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The accelerated expansion of the Universe was proposed through the use of Type-Ia supernovae (SNe) as standard candles. The standardization depends on an empirical correlation between the stretch/color and peak luminosity of the light curves. The use of Type-Ia SNe as standard candles rests on the assumption that their properties (and this correlation) do not vary with redshift. We consider the possibility that the majority of Type-Ia SNe are in fact caused by a Quark-Nova detonation in a tight neutron-star-CO-white-dwarf binary system, which forms a Quark-Nova Ia (QN-Ia). The spin-down energy injected by the Quark-Nova remnant (the quark star) contributes to the post-peak light curve and neatly explains the observed correlation between peak luminosity and light curve shape. We demonstrate that the parameters describing QN-Ia are NOT constant in redshift. Simulated QN-Ia light curves provide a test of the stretch/color correlation by comparing the true distance modulus with that determined using SN light curve fitters. We determine a correction between the true and fitted distance moduli, which when applied to Type-Ia SNe in the Hubble diagram recovers the ΩM = 1 cosmology. We conclude that Type-Ia SNe observations do not necessitate the need for an accelerating expansion of the Universe (if the observed SNe Ia are dominated by QNe Ia) and by association the need for dark energy. 相似文献
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地图是客观世界的摹写与抽象。但是“地图作为一种书写,它却只是给了阅读者一个绘制者眼中的世界,这世界的大小、上下、方位、比例,都渗透了绘制者的观念。”(葛兆光,《中国思想史》第二卷)这里所说的观念就是制图者的宇宙观,或者说是制作地图的那个时代的流行的宇宙观。我们知道,宇是指空间,即古人所说的上下四方,宙是指时间,即古人所说的古往今来。因此,从宇宙观的角度说,地图 相似文献
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基督教的经典是《圣经》,它包括《旧约》和《新约》。《圣经》毕竟是一部关于宗教及伦理的著作,而不是一部系统研究世界地理问题的地理学专著,它在地理学方面的描述是非常含混不清的,据说伏尔泰曾说过:“上帝显然不是地理学的行家。”《圣经》对于宇宙与世界的看法,是通过一些简单、模糊、分散的文句反映出来的。 相似文献