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Calculating Radiation Temperature Anisotropy in Flat Space Cosmology
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2018年第10期1946-1953,共8页
The purpose of this paper is to show how one can use the FSC model of gravitational entropy to calculate cosmic radiation temperature anisotropy for any past cosmic time t since the Planck scale. Cosmic entropy follow... The purpose of this paper is to show how one can use the FSC model of gravitational entropy to calculate cosmic radiation temperature anisotropy for any past cosmic time t since the Planck scale. Cosmic entropy follows the Bekenstein-Hawking definition, although in the correct-scaling form of, which scales 60.63 logs of 10 from the Planck scale. In the FSC model, cosmic radiation temperature anisotropy At = (t/to). The derived past anisotropy value can be compared to current co-moving anisotropy defined as unity (to/to). Calculated in this way, current gravitational entropy and temperature anisotropy have maximum values, and the earliest universe has the lowest entropy and temperature anisotropy values. This approach comports with the second law of thermodynamics and the theoretical basis of the Sachs-Wolfe effect, gravitational entropy as defined by Roger Penrose, and Erik Verlinde’s “emergent gravity” theory. 展开更多
关键词 FLAT SPACE cosmology cosmic microwave background CMB ANISOTROPY cosmology theory cosmic ENTROPY Gravitational ENTROPY Black Holes Standard cosmology
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Flat Space Cosmology as a Model of Penrose’s Weyl Curvature Hypothesis and Gravitational Entropy
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2018年第10期1935-1940,共6页
FSC is shown to be an excellent model of Penrose’s Weyl curvature hypothesis and his concept of gravitational entropy. The assumptions of FSC allow for the minimum entropy at the inception of the cosmic expansion and... FSC is shown to be an excellent model of Penrose’s Weyl curvature hypothesis and his concept of gravitational entropy. The assumptions of FSC allow for the minimum entropy at the inception of the cosmic expansion and rigorously define a cosmological arrow of time. This is in sharp contrast to inflationary models, which appear to violate the second law of thermodynamics within the early universe. Furthermore, by virtue of the same physical assumptions applying at any cosmic time t, the perpetually-flat FSC model predicts the degree of scale invariance observed in the CMB anisotropy pattern, without requiring an explosive and exceedingly brief inflationary epoch. Penrose’s concepts, as described in this paper, provide support for the idea that FSC models gravitational entropy and Verlinde’s emergent gravity theory. 展开更多
关键词 FLAT Space cosmology cosmology theory GRAVITATIONAL ENTROPY Weyl’s Curvature HYPOTHESIS Black Holes cosmic Inflation cosmic Flatness cosmic microwave background
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Predicted Dark Matter Quantitation in Flat Space Cosmology
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2018年第8期1559-1563,共5页
The purpose of this paper is to show how the dark matter predictions of FSC differ with respect to the standard cosmology assertion of a universal dark matter-to-visible matter ratio of approximately 5.3-to-1. FSC pre... The purpose of this paper is to show how the dark matter predictions of FSC differ with respect to the standard cosmology assertion of a universal dark matter-to-visible matter ratio of approximately 5.3-to-1. FSC predicts the correct ratio to be approximately 9-to-1, based primarily on the universal observations of global spatial flatness in the context of general relativity. The FSC Friedmann equations incorporating a Lambda?&Lambda;?cosmological term clearly indicate that a spatially flat universe must have equality of the positive curvature (matter mass-energy) and negative curvature (dark energy) density components. Thus, FSC predicts that observations of the Milky Way and the nearly co-moving galaxies within 100 million light years will prove the 5.3-to-1 ratio to be incorrect. The most recent galactic and perigalactic observations indicate a range of dark matter-to-visible matter ratios varying from essentially zero (NGC 1052-DF2) to approximately 23-to-1 (Milky Way). The latter ratio is simply astonishing and promises an exciting next few years for astrophysicists and cosmologists. Within the next few years, the mining of huge data bases (especially the Gaia catalogue and Hubble data) will resolve whether standard cosmology will need to change its current claims for the cosmic energy density partition to be more in line with FSC, or whether FSC is falsified. A prediction is that standard cosmology must eventually realize the necessity of resolving the tension between their flatness observations and their assertion of dark energy dominance. The author makes the further prediction that FSC will soon become the new paradigm in cosmology. 展开更多
关键词 FLAT SPACE cosmology Standard cosmology cosmology theory Dark Matter cosmic microwave background PLANCK Collaboration GRAVITATIONAL Entropy Black Holes
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宇宙微波背景辐射的观测和理论 被引量:3
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作者 冯珑珑 向守平 《天文学进展》 CSCD 北大核心 1999年第4期357-365,共9页
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各向异性形成的各种机制;展望了下一代宇宙微波背景探... 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各向异性形成的各种机制;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。 展开更多
关键词 宇宙学 宇宙 微波背景辐射 宇宙观测
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大爆炸宇宙学模型的基本参数──宇宙年龄t_0和哈勃常数H_0 被引量:2
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作者 向守平 《天文学进展》 CSCD 北大核心 1996年第3期219-226,共8页
大爆炸宇宙学模型有6个基本参数一宇宙年龄t0,哈勃常数H0(或哈勃参数h≡H0/100km·s-1·MPc-1),宇宙物质密度参数Ω0,减速因子q0,以及与宇宙学常数A和宇宙的曲率k有关的另外两个参数Ω0A≡A/3H,ΩR≡-K/H。简要介... 大爆炸宇宙学模型有6个基本参数一宇宙年龄t0,哈勃常数H0(或哈勃参数h≡H0/100km·s-1·MPc-1),宇宙物质密度参数Ω0,减速因子q0,以及与宇宙学常数A和宇宙的曲率k有关的另外两个参数Ω0A≡A/3H,ΩR≡-K/H。简要介绍了国际上对t0和H0的最近研究进展。由于观测上和理论上都还存在着相当多的不确定因素,目前对这两个参数的取值大小仍然有很大的争议。总的说来,对于宇宙的年龄t0,较普遍的看法是t>11Gyr,其最可见值为t0≈13Ggr。对于哈勃常数H0,如果所测的天体距离尺度较小,则通常给出较大的值h≈0.6-08;而如果所测天体距离尺度较大,则通常给出较小的值h≈0.4-0.6。最近哈勃空间望远镜对M100的观测绘出h≈0.8,这一测量结果仍然含有不确定因素,因而还不能认为H0的大小已有定论。 展开更多
关键词 宇宙年龄 爆炸宇宙学 宇宙模型 基本参数
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Overview of Hypersphere World-Universe Model 被引量:14
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2016年第4期593-632,共40页
This paper provides an overview of the Hypersphere World-Universe Model (WUM). WUM unifies and simplifies existing cosmological models and results into a single coherent picture, and proceeds to discuss the origin, ev... This paper provides an overview of the Hypersphere World-Universe Model (WUM). WUM unifies and simplifies existing cosmological models and results into a single coherent picture, and proceeds to discuss the origin, evolution, structure, ultimate fate, and primary parameters of the World. WUM explains the experimental data accumulated in the field of Cosmology and Astroparticle Physics over the last decades: the age of the world and critical energy density;the gravitational parameter and Hubble’s parameter;temperatures of the cosmic microwave background radiation and the peak of the far-infrared background radiation;gamma-ray background and cosmic neutrino background;macrostructure of the world and macroobjects structure. Additionally, the model makes predictions pertaining to masses of dark matter particles, photons, and neutrinos, proposes new types of particle interactions (Super Weak and Extremely Weak), and shows inter-connectivity of primary cosmological parameters of the world and the rise of the solar luminosity during the last 4.6 Byr. The model proposes to introduce a new fundamental parameter Q in the CODATA internationally recommended values. 展开更多
关键词 Hypersphere World-Universe Model Medium of the World Macroobjects Structure Gravitoelectromagnetism Dark Matter Particles Intergalactic Plasma microwave background Radiation Far-Infrared background Radiation Gamma-Ray background Radiation cosmic Neutrino background Q-Dependent Cosmological Parameters Emergent Phenomena Grand Unified theory CODATA
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Reconstruction of Gas Temperature and Density Profiles of the Galaxy Cluster RX J1347.5–1145
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作者 Qiang Yuan Tong-Jie Zhang Bao-Quan Wang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第6期671-676,共6页
We use observations of Sunyaev-Zel'dovich effect and X-ray surface brightness to reconstruct the radial profiles of gas temperature and density under the assumption of a spherically symmetric distribution of the gas.... We use observations of Sunyaev-Zel'dovich effect and X-ray surface brightness to reconstruct the radial profiles of gas temperature and density under the assumption of a spherically symmetric distribution of the gas. The method of reconstruction, first raised by Silk & White, depends directly on the observations of the Sunyaev-Zel'dovich effect and the X-ray surface brightness, without involving additional assumptions such as the equation of state of the gas or the conditions of hydrostatic equilibrium. We applied this method to the cluster RX J1347.5-1145, which has both the Sunyaev-Zel'dovich effect and X-ray observa- tions with relative high precision. It is shown that it will be an effective method to obtain the gas distribution in galaxy clusters. Statistical errors of the derived temperature and density profiles of gas were estimated according to the observational uncertainties. 展开更多
关键词 X-rays GALAXIES CLUSTERS cosmology theory cosmic microwave background galaxies: clusters: individual (RX J1347.5-1145)
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Relativist ic Corrections to the Thermal Sunyaev-Zel'dovich Power Spectrum
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作者 Hai-Ning LiNational Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 lhnDepartment of Astronomy, Beijing Normal University, Beijing 100875 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2003年第5期410-414,共5页
We present a quantitative estimate of the relativistic corrections to thethermal SZ power spectrum produced by the energetic electrons in massive clusters. The correctionsare well within 10% for current experiments wi... We present a quantitative estimate of the relativistic corrections to thethermal SZ power spectrum produced by the energetic electrons in massive clusters. The correctionsare well within 10% for current experiments with working frequencies below ν < 100 GHz, but becomenon-negligible at high frequencies ν > 350 GHz. Moreover, the corrections appear to be slightlysmaller at higher l or smaller angular scales. We conclude that there is no need to include therelativistic corrections in the theoretical study of the SZ power spectrum especially at lowfrequencies unless the SZ power spectrum is used for precision cosmology. 展开更多
关键词 cosmic microwave background cosmology: theory galaxies: clusters: general
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The interpretation of the CMBR
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作者 Yi-Jia Zheng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第9期180-184,共5页
In the popular ACDM model,the cosmic microwave background radiation(CMBR)is thought to be the remnant of the early hot universe.An important precondition of this interpretation of CMBR is:after the last scattering sur... In the popular ACDM model,the cosmic microwave background radiation(CMBR)is thought to be the remnant of the early hot universe.An important precondition of this interpretation of CMBR is:after the last scattering surface formed,the high temperature ionized gases in the universe became low temperature neutral gases and so the universe has been completely transparent to the radiation which comes from the hot early universe.However,observations show that today most gases in the universe are still in a high temperature ionized state.The universe is not completely transparent to the radiation which comes from the hot early universe.According to the famous Sunyaev-Zeldovich effect,if the CMBR comes from the early hot universe and follows a perfect blackbody spectrum,the free electrons in the cosmic plasma will distort the perfect blackbody spectrum of the CMBR.In this case,the observed CMBR cannot be of a perfect blackbody spectrum.This is a fatal flaw in the interpretation of CMBR using the ACDM model.In order to overcome this fatal flaw,in this paper it is proposed that in the ACDM model frame,a better interpretation of CMBR is:The CMBR is a thermal equilibrium product between the high temperature ionized gases and the cosmic radiation field in the local universe space. 展开更多
关键词 cosmology:theory cosmological model cosmic microwave background radiation
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How the CMB Anisotropy Pattern Could Be a Map of Gravitational Entropy
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2018年第8期1484-1490,共7页
The rationale for Flat Space Cosmology (FSC) calculations of gravitational entropy in the form ofis presented. These calculations indicate a tight correlation with the COBE DMR measurement showing CMB RMS temperature ... The rationale for Flat Space Cosmology (FSC) calculations of gravitational entropy in the form ofis presented. These calculations indicate a tight correlation with the COBE DMR measurement showing CMB RMS temperature variations of 18 micro Kelvins. The COBE dT/T anisotropy ratio of 0.66 × 10&minus;5 falls within the FSC gravitational entropy range calculated for the beginning and ending conditions of the recombination/decoupling epoch. Thus, the FSC model incorporating gravity as an emergent property of entropy suggests that the CMB temperature anisotropy pattern could simply be a map of gravitational entropy, as opposed to a magnified “quantum fluctuation” event at a finite beginning of time. 展开更多
关键词 Flat Space cosmology cosmic microwave background CMB ANISOTROPY cosmology theory cosmic ENTROPY GRAVITATIONAL ENTROPY Black Holes Standard cosmology
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