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利用引力波探测宇宙膨胀历史
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作者 朱良贵 陈弦 《物理》 北大核心 2025年第7期461-470,共10页
宇宙膨胀历史的信息反映在银河系外天体的距离和红移的关系中。引力波探测允许观测者直接测量引力波源的光度距离,而以电磁波为信使的传统天文观测可以测量引力波源的红移信息,两者结合可以用于探测宇宙的膨胀历史。2017年,LIGO和Virgo... 宇宙膨胀历史的信息反映在银河系外天体的距离和红移的关系中。引力波探测允许观测者直接测量引力波源的光度距离,而以电磁波为信使的传统天文观测可以测量引力波源的红移信息,两者结合可以用于探测宇宙的膨胀历史。2017年,LIGO和Virgo利用双中子星并合引力波事件GW170817的多信使联合观测,首次实现了利用引力波对宇宙膨胀速度的测量。利用引力波探测宇宙膨胀历史不依赖于传统电磁观测的测距方式,可以作为解决当前宇宙学危机的极具潜力的手段。文章将介绍利用引力波探测宇宙膨胀历史的基本原理、目前的探测结果和未来的预期表现,以及待解决的问题。 展开更多
关键词 引力波探测 标准汽笛 哈勃常数 暗能量状态方程 宇宙膨胀
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Quantum Cosmology: Cosmology Directly Linked to the Planck Scale in General Relativity Theory and Newton Gravity: The Link between Microcosmos and Cosmos
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作者 Espen Gaarder Haug 《Open Journal of Microphysics》 2025年第1期1-23,共23页
In this paper, we will demonstrate that there is a link between cosmology and the Planck scale. It has, in recent years, been shown that the Planck length can be determined independently of G, ℏ, and c, and that a ser... In this paper, we will demonstrate that there is a link between cosmology and the Planck scale. It has, in recent years, been shown that the Planck length can be determined independently of G, ℏ, and c, and that a series of cosmological predictions can be derived solely from two constants, namely the Planck length and the speed of gravity. The speed of gravity can be easily determined without knowledge of the speed of light [1] [2]. This provides a new perspective on cosmology and demonstrates that there is a link between the Planck scale and cosmology. This is fully consistent with a recent quantization of general relativity theory that links general relativity to the Compton frequency and the Planck scale. We examine both the Friedmann cosmology and the recently introduced cosmology based on the extremal solution of the Reissner-Nordström, Kerr, and Kerr-Newman metric.1. 展开更多
关键词 Hubble Constant Hubble Radius Universe Equation Freedman Universe Extremal Universe Planck Length Compton Length
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引力透镜与引力波宇宙学
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作者 木成盛 曹硕 《物理》 北大核心 2025年第7期451-460,共10页
引力透镜与引力波是爱因斯坦广义相对论的两个重要预言。引力透镜早已成为丰富的天文观测现象和强有力的天体物理手段,引力波的直接探测则为人类探索宇宙打开了另外一扇全新的窗口。文章阐述透镜化引力波在当今天文学中的重要意义,重点... 引力透镜与引力波是爱因斯坦广义相对论的两个重要预言。引力透镜早已成为丰富的天文观测现象和强有力的天体物理手段,引力波的直接探测则为人类探索宇宙打开了另外一扇全新的窗口。文章阐述透镜化引力波在当今天文学中的重要意义,重点论述引力波的透镜现象及其在现代宇宙学中的独特应用。首先回顾电磁波引力透镜的理论基础和观测历史,详细讨论透镜化引力波的独特性(包括其在时间延迟测量上的高精度优势以及波动光学效应带来的复杂调制模式)。之后详细介绍三种识别透镜化引力波信号的方法,及其在暗物质和其子结构探测、哈勃常数精确测量、区分暗能量与修正引力理论等方面的最新应用。最后强调未来地面—空间引力波探测器在此领域的重要作用,并期待其成为现代宇宙学研究中不可或缺的强大工具。 展开更多
关键词 引力透镜 引力波 宇宙学 暗物质 哈勃常数 暗能量
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改进YOLOv5s算法的带钢表面缺陷检测 被引量:3
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作者 王林琳 龚昭昭 梁泽启 《组合机床与自动化加工技术》 北大核心 2024年第12期181-186,共6页
针对带钢表面缺陷小目标检测精度低以及检测效率低等问题,提出了一种基于YOLOv5s的带钢表面缺陷检测算法。首先,增加一个大尺度预测层,通过更丰富的位置信息提高小目标缺陷的检测效果,减少漏检和误检的问题;其次,将Shuffle Netv2轻量化... 针对带钢表面缺陷小目标检测精度低以及检测效率低等问题,提出了一种基于YOLOv5s的带钢表面缺陷检测算法。首先,增加一个大尺度预测层,通过更丰富的位置信息提高小目标缺陷的检测效果,减少漏检和误检的问题;其次,将Shuffle Netv2轻量化骨干网络替换原来的CSPDarknet53网络结构,降低模型参数数量,加快模型推理速度;然后,在特征提取网络末端添加基于Transformer编码的C3TR模块以及在特征融合网络中添加CA注意力机制,增强网络对缺陷的特征提取能力;最后,引入WIoU损失函数来取代GIoU,提高回归精度。实验结果表明,改进后的YOLOv5s算法在武汉某钢厂采集的带钢表面缺陷数据集上平均准确率(mAP)达到92.2%,较原始YOLOv5s提高了4.7%,检测速度FPS达到了82,具有较高检测精度。并引入公开数据集进行泛化实验,结果均有显著提升,进一步满足了对带钢表面缺陷检测的需求。 展开更多
关键词 钢材表面缺陷 YOLOv5s Shuffle Netv2 C3TR模块 CA注意力机制 WIoU损失函数
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哈勃空间望远镜运行控制及规划模式研究综述
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作者 张爱成 邹雪梅 +1 位作者 陈翔 朱常明 《兵工学报》 EI CAS CSCD 北大核心 2024年第S02期36-46,共11页
哈勃空间望远镜(Hubble Space Telescope,HST)作为首个大型且复杂的在轨空间天文观测站,其成功运行离不开NASA的主导及多个控制中心与机构的协同努力。深入探讨了哈勃任务的多机构协同管理模式,详细分析了运控中心飞行操作人员的构成及... 哈勃空间望远镜(Hubble Space Telescope,HST)作为首个大型且复杂的在轨空间天文观测站,其成功运行离不开NASA的主导及多个控制中心与机构的协同努力。深入探讨了哈勃任务的多机构协同管理模式,详细分析了运控中心飞行操作人员的构成及其执行的典型操控活动。同时,针对HST的数据上下行处理及转发测控模式进行了分析,并研究了其地面软件系统的架构及其自任务实施以来的升级改造情况。全面分析了哈勃开展天文观测任务的全规划流程及周期规划模式。基于哈勃任务的成功实施经验,为我国未来开展空间望远镜任务提供了具体且有益的启示。 展开更多
关键词 哈勃空间望远镜 运控中心 飞行操作 天文观测
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基于江苏海域定点观测资料的双峰谱谱型研究
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作者 杨伊妮 陶爱峰 +2 位作者 曹力玮 范骏 王岗 《海洋学报》 CAS CSCD 北大核心 2024年第2期107-116,共10页
江苏海域作为全国海上风电重点建设海域,走向远海是未来发展的主趋势,外海开敞海域涌浪成分较多,海浪谱往往以双峰谱的形式出现,因此双峰谱海浪的谱型特征需要进一步深入研究,为海上施工提供参考依据。基于浮标测站2018年全年观测数据,... 江苏海域作为全国海上风电重点建设海域,走向远海是未来发展的主趋势,外海开敞海域涌浪成分较多,海浪谱往往以双峰谱的形式出现,因此双峰谱海浪的谱型特征需要进一步深入研究,为海上施工提供参考依据。基于浮标测站2018年全年观测数据,经过异常值检验、双峰谱识别后得到1 223笔双峰谱数据,进而研究江苏海域波浪双峰谱谱型特征,对比不同典型双峰谱谱型并展开实测双峰谱的拟合,提出了修正谱宽参量,探究了修正系数、峰升高因子、谱宽参量间的依赖关系,得到了双峰谱拟合谱型表达式。结果表明:基于北大西洋海域提出Ochi-Hubble谱系及基于挪威海域提出的Torsethaugen谱并不适用于江苏海域双峰谱谱型,本文提出的双峰JONSWAP拟合谱具有自适应性,可以科学合理地描述江苏海域双峰谱谱型,并推广应用于不同风场、地形条件的海域中。 展开更多
关键词 江苏海域 双峰谱 Ochi-Hubble六参数谱 Torsethaugen双峰谱 双峰JONSWAP拟合谱
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Hubble Tension Explanation from This Cosmological Model AΛΩ (Slow Bang Model, SB)
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作者 Jean Perron 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期106-125,共20页
In this article we present a model of Hubble-Lemaître law using the notions of a transmitter (galaxy) and a receiver (MW) coupled to a model of the universe (Slow Bang Model, SB), based on a quantum approach of t... In this article we present a model of Hubble-Lemaître law using the notions of a transmitter (galaxy) and a receiver (MW) coupled to a model of the universe (Slow Bang Model, SB), based on a quantum approach of the evolution of space-time as well as an equation of state that retains all the infinitesimal terms. We find an explanation of the Hubble tension H<sub>0</sub>. Indeed, we have seen that this constant depends on the transceiver pair which can vary from the lowest observable value, from photons of the CMB (theoretical [km/s/Mpc]) to increasingly higher values depending on the earlier origin of the formation of the observed galaxy or cluster (ETG ~0.3 [Gy], ~74 [km/s/Mpc]). We have produced a theoretical table of the values of the constant according to the possible pairs of transmitter/receiver in the case where these galaxies follow the Hubble flow without large disturbance. The calculated theoretical values of the constant are in the order of magnitude of all values mentioned in past studies. Subsequently, we applied the models to 9 galaxies and COMA cluster and found that the models predict acceptable values of their distances and Hubble constant since these galaxies mainly follow the Hubble flow rather than the effects of a galaxy cluster or a group of clusters. In conclusion, we affirm that this Hubble tension does not really exist and it is rather the understanding of the meaning of this constant that is questioned. 展开更多
关键词 Model of the Universe Cosmological Constant Hubble Constant Hubble’s Tension Hubble-Lemaître Law Hubble’s Flow
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On a Cosmological Model with Variable Time Flow
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作者 Ralph Gramigna 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1514-1530,共17页
The Friedmann-Lemaître-Robertson-Walker (FLRW) metric is an exact solution of the Einstein field equations and it describes a homogeneous, isotropic and expanding universe. The FLRW metric and the Friedmann equat... The Friedmann-Lemaître-Robertson-Walker (FLRW) metric is an exact solution of the Einstein field equations and it describes a homogeneous, isotropic and expanding universe. The FLRW metric and the Friedmann equations form the basis of the ΛCDM model. In this article, a metric which is based on the FLRW metric and that includes a space scale factor and a newly introduced time scale factor T(t)is elaborated. The assumption is that the expansion or contraction of the dimensions of space and time in a homogeneous and isotropic universe depend on the energy density. The Christoffel symbols, Ricci tensor and Ricci scalar are derived. By evaluating the results using Einstein’s field equations and the energy momentum tensor, a hypothetical modified cosmological model is obtained. This theoretical model provides for a cosmic inflation, the accelerated expansion of spacetime as well avoids the flatness and fine-tuning problems. 展开更多
关键词 COSMOLOGY Dark Energy Cosmic Inflation Flatness Problem Hubble Tension
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Restoring cosmological concordance with axion-like early dark energy and dark matter characterized by a constant equation of state?
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作者 Yan-Hong Yao Xin-He Meng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第7期74-82,共9页
The Hubble tension persists as a challenge in cosmology.Even early dark energy(EDE)models,initially considered the most promising for alleviating the Hubble tension,fall short of addressing the issue without exacerbat... The Hubble tension persists as a challenge in cosmology.Even early dark energy(EDE)models,initially considered the most promising for alleviating the Hubble tension,fall short of addressing the issue without exacerbating other tensions,such as the S_(8)tension.Considering that a negative dark matter(DM)equation of state(EoS)parameter is conducive to reduce the value of the σ_(8)parameter,we extend the axion-like EDE model in this paper by replacing the cold dark matter(CDM)with DM characterized by a constant EoS w_(dm)(referred to as WDM hereafter).We then impose constraints on this axion-like EDE extension model,along with three other models:the axion-like EDE model,ΛWDM,and ΛCDM.These constraints are derived from a comprehensive analysis incorporating data from the Planck 2018 cosmic microwave background,baryon acoustic oscillations,and the Pantheon compilation,as well as a prior on H_(0)(i.e.H_(0)=73.04±1.04,based on the latest local measurement by Riess et al)and a Gaussianized prior on S_(8)(i.e.S_(8)=0.766±0.017,determined through the joint analysis of KID1000+BOSS+2dLenS).We find that although the new model maintains the ability to alleviate the Hubble tension to~1.4σ,it still exacerbates the S_(8)tension to a level similar to that of the axion-like EDE model. 展开更多
关键词 Hubble tension early dark energy noncold dark matter S8 tension
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Heuristic Estimation of the Vacuum Energy Density of the Universe: Part II-Analysis Based on Frequency Domain Electromagnetic Radiation
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作者 Vernon Cooray Gerald Cooray +1 位作者 Marcos Rubinstein Farhad Rachidi 《Journal of Electromagnetic Analysis and Applications》 2024年第1期1-9,共9页
In Part I of this paper, an inequality satisfied by the vacuum energy density of the universe was derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according ... In Part I of this paper, an inequality satisfied by the vacuum energy density of the universe was derived using an indirect and heuristic procedure. The derivation is based on a proposed thought experiment, according to which an electron is accelerated to a constant and relativistic speed at a distance L from a perfectly conducting plane. The charge of the electron was represented by a spherical charge distribution located within the Compton wavelength of the electron. Subsequently, the electron is incident on the perfect conductor giving rise to transition radiation. The energy associated with the transition radiation depends on the parameter L. It was shown that an inequality satisfied by the vacuum energy density will emerge when the length L is pushed to cosmological dimensions and the product of the radiated energy, and the time duration of emission is constrained by Heisenberg’s uncertainty principle. In this paper, a similar analysis is conducted with a chain of electrons oscillating sinusoidally and located above a conducting plane. In the thought experiment presented in this paper, the behavior of the energy radiated by the chain of oscillating electrons is studied in the frequency domain as a function of the length L of the chain. It is shown that when the length L is pushed to cosmological dimensions and the energy radiated within a single burst of duration of half a period of oscillation is constrained by the fact that electromagnetic energy consists of photons, an inequality satisfied by the vacuum energy density emerges as a result. The derived inequality is given by where is the vacuum energy density. This result is consistent with the measured value of the vacuum energy density, which is 5.38 × 10<sup>-10</sup> J/m. The result obtained here is in better agreement with experimental data than the one obtained in Part I of this paper with time domain radiation. 展开更多
关键词 Classical Electrodynamics Electromagnetic Radiation Action Radiated Energy PHOTON Heisenberg’s Uncertainty Principle Dark Energy Vacuum Energy Cosmological Constant Hubble Radius
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JWST Discoveries and the Hypersphere World-Universe Model: Transformative New Cosmology
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1806-1834,共29页
Twenty-six years ago, a small committee report built upon earlier studies to articulate a compelling and poetic vision for the future of astronomy. This vision called for an infrared-optimized space telescope with an ... Twenty-six years ago, a small committee report built upon earlier studies to articulate a compelling and poetic vision for the future of astronomy. This vision called for an infrared-optimized space telescope with an aperture of at least four meters. With the support of their governments in the US, Europe, and Canada, 20,000 people brought this vision to life as the 6.5-meter James Webb Space Telescope (JWST). The telescope is working perfectly, delivering much better image quality than expected [1]. JWST is one hundred times more powerful than the Hubble Space Telescope and has already captured spectacular images of the distant universe. A view of a tiny part of the sky reveals many well-formed spiral galaxies, some over thirteen billion light-years away. These observations challenge the standard Big Bang Model (BBM), which posits that early galaxies should be small and lack well-formed spiral structures. JWST’s findings are prompting scientists to reconsider the BBM in its current form. Throughout the history of science, technological advancements have led to new results that challenge established theories, sometimes necessitating their modification or even abandonment. This happened with the geocentric model four centuries ago, and the BBM may face a similar reevaluation as JWST provides more images of the distant universe. In 1937, P. Dirac proposed the Large Number Hypothesis and the Hypothesis of Variable Gravitational Constant, later incorporating the concept of Continuous Creation of Matter in the universe. The Hypersphere World-Universe Model (WUM) builds on these ideas, introducing a distinct mechanism for matter creation. WUM is proposed as an alternative to the prevailing BBM. Its main advantage is the elimination of the “Initial Singularity” and “Inflation”, offering explanations for many unresolved problems in Cosmology. WUM is presented as a natural extension of Classical Physics with the potential to bring about a significant transformation in both Cosmology and Classical Physics. Considering JWST’s discoveries, WUM’s achievements, and 87 years of Dirac’s proposals, it is time to initiate a fundamental transformation in Astronomy, Cosmology, and Classical Physics. The present paper is a continuation of the published article “JWST Discoveries—Confirmation of World-Universe Model Predictions” [2] and a summary of the paper “Hypersphere World-Universe Model: Digest of Presentations John Chappell Natural Philosophy Society” [3]. Many results obtained there are quoted in the current work without full justification;interested readers are encouraged to view the referenced papers for detailed explanations. 展开更多
关键词 World-Universe Model JWST Discoveries Universe-Created Matter Gravity GRAVITOMAGNETISM Wave-Particle Duality Hubble Tension Stretching of World Dark Epoch Luminous Epoch Axis of Evil
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Universe Expansion and Gravitation Unified
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作者 Antonio Medina 《International Journal of Astronomy and Astrophysics》 2024年第4期259-276,共18页
Aims: The expansion of the Universe and gravitation are considered different fundamental properties of the cosmos. We explore whether they are connected and propose an equation that links and unifies them. This equati... Aims: The expansion of the Universe and gravitation are considered different fundamental properties of the cosmos. We explore whether they are connected and propose an equation that links and unifies them. This equation describes the expansion of space as related to the mass of matter in that space. An expanding frame of reference, defined as expanding at the same rate, is the natural frame for an observer since the observer is part of the Universe and expands with it. In this frame, the expansion of the Universe by itself accounts for phenomena previously ascribed to gravitation. Gravity is fictitious and unnecessary. Here, we show that universal expansion naturally manifests as “gravity”. Methods: A theory is presented that postulates a natural expansion of the observer’s frame of reference due to matter and a generalized universal principle of equivalence of acceleration and gravitation that extends to any frame. It is consistent with both the general theory of relativity and our knowledge about the expansion of the Universe. Results: We tested the theory positively by applying its equation to global and local scales of the Universe with available data. It is applied to a Universe of homogeneous mass and discrete two and three-body systems and other phenomena hitherto thought to be unrelated. The results show that the proposed equation is valid at any scale. The fundamental nature of the Universe, from which gravity and other properties are derived, is its expansion. 展开更多
关键词 GRAVITATION UNIVERSE Cosmological Theories Visible Universe Hubble Expansion Cosmological Models Flat Space Cosmology Dark Energy Dark Matter Hubble Parameter Critical Density
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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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Predicting High Precision Hubble Constant Determinations Based on a New Theoretical Relationship between CMB Temperature and H0
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作者 Eugene Terry Tatum Espen Gaarder Haug Stéphane Wojnow 《Journal of Modern Physics》 2024年第11期1708-1716,共9页
Based on considerable progress made in understanding the Cosmic Microwave Background (CMB) temperature from a deep theoretical perspective, this paper demonstrates a useful and simple relationship between the CMB temp... Based on considerable progress made in understanding the Cosmic Microwave Background (CMB) temperature from a deep theoretical perspective, this paper demonstrates a useful and simple relationship between the CMB temperature and the Hubble constant. This allows us to predict the Hubble constant with much higher precision than before by using the CMB temperature. This is of great importance, since it will lead to much higher precision in various global parameters of the cosmos, such as the Hubble radius and the age of the universe. We have improved uncertainty in the Hubble constant all the way down to 66.8712 ± 0.0019 km/s/Mpc based on data from one of the most recent CMB studies. Previous studies based on other methods have rarely reported an uncertainty much less than approximately ±1 km/s/Mpc for the Hubble constant. Our deeper understanding of the CMB and its relation to H0seems to be opening a new era of high-precision cosmology, which may well be the key to solving the Hubble tension, as alluded to herein. Naturally, our results should also be scrutinized by other researchers over time, but we believe that, even at this stage, this deeper understanding of the CMB deserves attention from the research community. 展开更多
关键词 Hubble Constant CMB Planck Temperature Upsilon Constant
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Cosmological Implications of Diffusion: The Hubble Tension
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作者 Sebastiano Tosto 《Journal of Applied Mathematics and Physics》 2024年第12期4077-4097,共21页
The paper introduces an “ab initio” model to calculate the timeline of the temperature field of the Big Bang radiation field in the universe and its connection with the Hubble law. The theoretical approach is rooted... The paper introduces an “ab initio” model to calculate the timeline of the temperature field of the Big Bang radiation field in the universe and its connection with the Hubble law. The theoretical approach is rooted in the concept of quantum uncertainty and has a quantum character. The aim is to emphasize that the big bang energy diffusion throughout the expanding universe is enough to account also for the Hubble tension. 展开更多
关键词 Quantum Theory RELATIVITY Universe Timeline Universe Age Hubble Tension
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How to Predict the Temperature of the CMB Directly Using the Hubble Parameter and the Planck Scale Using the Stefan-Boltzmann Law
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作者 Espen Gaarder Haug Stéphane Wojnow 《Journal of Applied Mathematics and Physics》 2024年第10期3552-3566,共15页
Based on recent progress in quantum gravity and quantum cosmology, we are also presenting a way to estimate the temperature in the cosmos, the Hubble sphere, from a relation between the Planck temperature and the Hubb... Based on recent progress in quantum gravity and quantum cosmology, we are also presenting a way to estimate the temperature in the cosmos, the Hubble sphere, from a relation between the Planck temperature and the Hubble scale. Our analysis predicts the Hubble sphere temperature of 2.72 K with the one standard deviation confidence interval between 2.65 K and 2.80 K, which corresponds well with the measured temperature observed from the cosmic microwave background (CMB) of about 2.72 K. This adds evidence that there is a close connection between the Planck scale, gravity, and the cosmological scales as anticipated by Eddington already in 1918.1. 展开更多
关键词 CMB Temperature Hubble Parameter Stefan-Boltzmann Law Planck Scale
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The Hawking Hubble Temperature as the Minimum Temperature, the Planck Temperature as the Maximum Temperature, and the CMB Temperature as Their Geometric Mean Temperature
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作者 Espen Gaarder Haug Eugene Terry Tatum 《Journal of Applied Mathematics and Physics》 2024年第10期3328-3348,共21页
Using a rigorous mathematical approach, we demonstrate how the Cosmic Microwave Background (CMB) temperature could simply be a form of geometric mean temperature between the minimum time-dependent Hawking Hubble tempe... Using a rigorous mathematical approach, we demonstrate how the Cosmic Microwave Background (CMB) temperature could simply be a form of geometric mean temperature between the minimum time-dependent Hawking Hubble temperature and the maximum Planck temperature of the expanding universe over the course of cosmic time. This mathematical discovery suggests a re-consideration of Rh=ctcosmological models, including black hole cosmological models, even if it possibly could also be consistent with the Λ-CDM model. Most importantly, this paper contributes to the growing literature in the past year asserting a tightly constrained mathematical relationship between the CMB temperature, the Hubble constant, and other global parameters of the Hubble sphere. Our approach suggests a solid theoretical framework for predicting and understanding the CMB temperature rather than solely observing it.1. 展开更多
关键词 Hawking Temperature Planck Temperature CMB Temperature Geometric Mean Compton Wavelength Hubble Sphere Cosmological Models
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Upsilon Constants and Their Usefulness in Planck Scale Quantum Cosmology
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2024年第2期167-173,共7页
This paper introduces the two Upsilon constants to the reader. Their usefulness is described with respect to acting as coupling constants between the CMB temperature and the Hubble constant. In addition, this paper su... This paper introduces the two Upsilon constants to the reader. Their usefulness is described with respect to acting as coupling constants between the CMB temperature and the Hubble constant. In addition, this paper summarizes the current state of quantum cosmology with respect to the Flat Space Cosmology (FSC) model. Although the FSC quantum cosmology formulae were published in 2018, they are only rearrangements and substitutions of the other assumptions into the original FSC Hubble temperature formula. In a real sense, this temperature formula was the first quantum cosmology formula developed since Hawking’s black hole temperature formula. A recent development in the last month proves that the FSC Hubble temperature formula can be derived from the Stephan-Boltzmann law. Thus, this Hubble temperature formula effectively unites some quantum developments with the general relativity model inherent in FSC. More progress towards unification in the near-future is expected. 展开更多
关键词 Quantum Cosmology Hubble Constant Planck Scale Upsilon Constant Flat Space Cosmology Black Holes CMB Temperature ΛCDM Cosmology Quantum Gravity Unification
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Predicting Dark Energy Survey Results within the Haug-Tatum Cosmology Model
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作者 Eugene Terry Tatum Espen Gaarder Haug 《Journal of Modern Physics》 2024年第12期2220-2227,共8页
Given the pending completion and publication of the final Dark Energy Survey (DESI) results, this letter presents the corresponding predictions of the Haug-Tatum cosmology (HTC) model. In particular, we show in tabula... Given the pending completion and publication of the final Dark Energy Survey (DESI) results, this letter presents the corresponding predictions of the Haug-Tatum cosmology (HTC) model. In particular, we show in tabular and graphic form the “dark energy decay” curve which the HTC model predicts for cosmological redshifts covering the range of 0 - 2.0 z. Furthermore, we present the HTC model distance-vs-redshift curve in comparison to the three very different curves (for luminosity distance, angular diameter distance, and co-moving distance) calculated within the Lambda-CDM model. Whether the expansion of our universe is actually undergoing slight acceleration or the finely-tuned cosmic coasting at constant velocity of Rh = ct models, including HTC, will hopefully soon be answered by the many pending observational studies. 展开更多
关键词 Haug-Tatum Cosmology Dark Energy Lambda-CDM Cosmology Cosmological Redshift Hubble Parameter Upsilon Constant DESI Rh = ct Cosmology
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Introducing a 2nd Universal Space-Time Constant Can Explain the Observed Age of the Universe and Dark Energy
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作者 Herman A. van Hoeve 《World Journal of Mechanics》 2024年第2期9-22,共14页
The purpose of this paper is to introduce new theoretical concepts as opposed to accepting the existence of dark entities, such as dark energy. This research sought to introduce a 2<sup>nd</sup> universal ... The purpose of this paper is to introduce new theoretical concepts as opposed to accepting the existence of dark entities, such as dark energy. This research sought to introduce a 2<sup>nd</sup> universal space-time constant, besides having a finite speed constant (speed of light in vacuum c). A finite universal age constant b is introduced. Namely, this paper shows that the changes in the Earth’s anomalistic year duration over time support the hypothesis of the age of the universe correlating with a maximum number of orbital revolutions constant. Neglecting the gravitational influence of other cosmological entities in the proximity of the Earth, the constant maximum number of revolutions is herewith determined solely by the Earth’s orbital revolutions around the Sun. The value of the universal age constant b is calculated to be around 13.8 billion orbital revolutions, derived out of an equation related to the changes in the Earth’s anomalistic year duration over time and the so-called Hubble tension. The above-mentioned calculated value b correlates well with the best fit to measured data of the cosmic microwave background radiation (CMBR) by the Planck spacecraft, the age of the observed universe is measured to be approximately 13.787 ± 0.020 billion years (2018 final data release). Developing a theory with this 2<sup>nd</sup> universal space-time constant b, being covariant with respect to the Lorentz transformations when time spans are large, gives results such as: A confirmation of the measured CMBR value of 13.787 ± 0.020 billion years. Correlating well with the observed expansion rate of the universe (dark energy). The universe’s expansion accelerating over the last four to five billion years. 展开更多
关键词 Anomalistic Year Orbital Revolution Hubble Tension Age of the Universe Cosmological Constant Dark Energy Cosmic Microwave Background
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