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A New Version of the Lambda-CDM Cosmological Model, with Extensions and New Calculations
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作者 Jan Helm 《Journal of Modern Physics》 2024年第2期193-238,共46页
This article gives a state-of-the-art description of the cosmological Lambda-CDM model and in addition, presents extensions of the model with new calculations of background and CMB functions. Chapters 1-4 describe the... This article gives a state-of-the-art description of the cosmological Lambda-CDM model and in addition, presents extensions of the model with new calculations of background and CMB functions. Chapters 1-4 describe the background part of the model, i.e. the evolution of scale factor and density according to the Friedmann equations, and its extension, which results in a correction of the Hubble parameter, in agreement with new measurements (Cepheids-SNIa and Red-Giants). Based on this improved background calculation presented in chapters 5-9 the perturbation part of the model, i.e. the evolution of perturbation and structure according to the perturbed Einstein equations and continuity-Euler equations, and the power spectrum of the cosmic microwave background (CMB) is calculated with a new own code. 展开更多
关键词 Lambda-DCM friedmann Equations CMB metric Perturbation Hubble Parameter
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Revised Newtonian Formula of Gravity and Equation of Cosmology in Flat Space-Time Transformed from Schwarzschild Solution
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作者 Xiaochun Mei Ping Yu 《International Journal of Astronomy and Astrophysics》 2012年第1期6-18,共13页
By transforming the geodesic equation of the Schwarzschild solution of the Einstein’s equation of gravity field to flat space-time for description, the revised Newtonian formula of gravity is obtained. The formula ca... By transforming the geodesic equation of the Schwarzschild solution of the Einstein’s equation of gravity field to flat space-time for description, the revised Newtonian formula of gravity is obtained. The formula can also describe the motion of object with mass in gravity field such as the perihelion precession of the Mercury. The space-time singularity in the Einstein’s theory of gravity becomes the original point r = 0 in the Newtonian formula of gravity. The singularity problem of gravity in curved space-time is eliminated thoroughly. When the formula is used to describe the expansive universe, the revised Friedmann equation of cosmology is obtained. Based on it, the high red-shift of Ia supernova can be explained well. We do not need the hypotheses of the universe accelerating expansion and dark energy again. It is also unnecessary for us to assume that non-baryon dark material is 5 - 6 times more than normal baryon material in the universe if they really exist. The problem of the universal age can also be solved well. The theory of gravity returns to the traditional form of dynamic description and becomes normal one. The revised equation can be taken as the foundation of more rational cosmology. 展开更多
关键词 General Relativity SCHWARZSCHILD metric COSMOLOGY friedmann Equation NEWTONIAN GRAVITY Supernova Hubble Constant DARK Material DARK Energy UNIVERSE Accelerating Expansion UNIVERSE Age
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均匀密度零压星的完整的引力解
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作者 陈光 《物理学报》 SCIE EI CAS CSCD 北大核心 2002年第1期197-200,共4页
证明了Oppenheimer和Snyder关于均匀密度零压星的引力塌缩的经典解是不完整的 ,它并不能正确地连接作为内解和外解的Friedmann度规和Schwarzschild度规 ;通过在离散时空上拓展解参数而构成了一个完整的引力解 ,它实现了Friedmann度规和S... 证明了Oppenheimer和Snyder关于均匀密度零压星的引力塌缩的经典解是不完整的 ,它并不能正确地连接作为内解和外解的Friedmann度规和Schwarzschild度规 ;通过在离散时空上拓展解参数而构成了一个完整的引力解 ,它实现了Friedmann度规和Schwarzschild度规之间的等价连接 ,并可以证明是奇性自由的 ;这个完整的引力解显示了物质 。 展开更多
关键词 均匀密度零压星 friedmann度规 SCHWARZSCHILD度规 离散时空 引力塌缩 完整引力解
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A Space Propulsion Principle Brought about by Locally-Expanded Space 被引量:1
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作者 Yoshinari Minami 《Journal of Earth Science and Engineering》 2014年第8期490-499,共10页
As is well known in cosmology, inflationary universe which shows rapid expansion of space is based on the phase transition of the vacuum exhibited by the Weinberg-Salam model of the electroweak interaction. The vacuum... As is well known in cosmology, inflationary universe which shows rapid expansion of space is based on the phase transition of the vacuum exhibited by the Weinberg-Salam model of the electroweak interaction. The vacuum has the property of a phase transition, just like water may become ice and vice versa. This shows that a vacuum possesses a substantial physical structure. The expansion rule of the universe is governed by the Friedmann equations and the Robertson-Walker metric. We explored another possibility of a space propulsion principle where the locally rapid expanding space generates the thrust, using the cosmology. In this paper, space propulsion principle is introduced from another angle (cosmology), that is, the pressure of the field induced by local expansion of space is completely considered in the propulsion principle. 展开更多
关键词 Space drive PROPULSION COSMOLOGY expanding universe friedmann equation Robertson-Walker metric de Sitteruniverse inflation.
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弗里德曼空间和宇宙论
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作者 张维广 《山东师范大学学报(自然科学版)》 CAS 1994年第3期5-10,共6页
利用弗里德曼空间理论,讨论了宇宙学中的一些问题,主要内容:(1)弗里德曼空间的度规张量;(2)弗里德曼空间的能量动量张量;(3)弗里德曼空间的演化和温度的关系;(4)红向移动的理论公式.
关键词 弗里德曼空间 宇宙论 度规张量 能量动量张量
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