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On Unobservability of One-Way Speed of Light 被引量:1
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作者 Yuan Zhong ZHANG (Institute of Theoretical Physics, Academia Sinica, P. O. Box 2735, Beijing 100080, China.) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1995年第4期253-264,共12页
In this paper we recall the different definitions of simultaneity, the coordinate time interval and the velocity. It is emphasized that the above second two definitions depend on the simultaneity. We review the test t... In this paper we recall the different definitions of simultaneity, the coordinate time interval and the velocity. It is emphasized that the above second two definitions depend on the simultaneity. We review the test theories on special relativity. It is shown that anisotropy (if possible) of one-way speed of light has not any ef- fects in the physical experiments. Therefore anisotropy of one-way speed of light cannot be determined by the experiments, except if an absolute (standard) simultaneity would be found. 展开更多
关键词 SIMULTANEITY one-way speed of light Test theory Special relativity
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Faster than the Speed of Light Is a Quantum Phenomena
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作者 Ardeshir Irani 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第2期379-382,共4页
Classical Mechanics using Einstein’s theories of relativity places a limit on speed as the speed of light. Quantum Mechanics has no such limitation. To understand space accelerating faster than the speed of light and... Classical Mechanics using Einstein’s theories of relativity places a limit on speed as the speed of light. Quantum Mechanics has no such limitation. To understand space accelerating faster than the speed of light and information being exchanged instantaneously between two entangled electrons separated by huge distances, one uses Planck’s length, Planck’s time, and Planck’s mass to indicate that space and time are discrete and therefore along with masses smaller than Planck’s mass are Quantum Mechanical in nature. Faster than the speed of light c = 3 × 10<sup>8</sup> m/s is a classical effect only in dimensions of space lower than our 3-D Universe, but it is a Quantum effect in all dimensions of space. Because space can oscillate sending out ripples from the source, it is the medium used for transporting light waves and gravity waves. 展开更多
关键词 Faster than the speed of light CLASSICAL QUANTUM Planck’s Units Space as a Medium Comparison with String Theory
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The Speed of Light Is Not Constant in Basic Big Bang Theory
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作者 Jef Van Royen 《Journal of Modern Physics》 CAS 2023年第3期287-310,共24页
Starting from the basic assumptions and equations of Big Bang theory, we present a simple mathematical proof that this theory implies a varying (decreasing) speed of light, contrary to what is generally accepted. We c... Starting from the basic assumptions and equations of Big Bang theory, we present a simple mathematical proof that this theory implies a varying (decreasing) speed of light, contrary to what is generally accepted. We consider General Relativity, the first Friedmann equation and the Friedmann-Lema?tre- Robertson-Walker (FLRW) metric for a Comoving Observer. It is shown explicitly that the Horizon and Flatness Problems are solved, taking away an important argument for the need of Cosmic Inflation. A decrease of 2.1 cm/s per year of the present-day speed of light is predicted. This is consistent with the observed acceleration of the expansion of the Universe, as determined from high-redshift supernova data. The calculation does not use any quantum processes, and no adjustable parameters or fine tuning are introduced. It is argued that more precise laboratory measurements of the present-day speed of light (and its evolution) should be carried out. Also it is argued that the combination of the FLRW metric and Einstein’s field equations of General Relativity is inconsistent, because the FLRW metric implies a variable speed of light, and Einstein’s field equations use a constant speed of light. If we accept standard Big Bang theory (and thus the combination of General Relativity and the FLRW metric), a variable speed of light must be allowed in the Friedmann equation, and therefore also, more generally, in Einstein’s field equations of General Relativity. The explicit form of this time dependence will then be determined by the specific problem. 展开更多
关键词 General Relativity Friedmann Equation Big Bang Cosmic Microwave Background CMB Varying speed of light Flatness Problem Horizon Problem Cosmic Inflation
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A Workable Solution for Reducing the Large Number of Vehicle and Pedestrian Accidents Occurring on a Yellow Light
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作者 Pranav Gupta Silki Arora 《Journal of Transportation Technologies》 2024年第1期82-87,共6页
Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the U.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada... Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the U.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada, during 2019, the National Collision Database shows that 28% of traffic fatalities and 42% of serious injuries occurred at intersections. Likewise, the U.S. National Highway Traffic Administration (NHTSA) found that about 40% of the estimated 5,811,000 accidents in the U.S. during the year studied were intersection-related crashes. In fact, a major survey by the car insurance industry found that nearly 85% of drivers could not identify the correct action to take when approaching a yellow traffic light at an intersection. One major reason for these accidents is the “yellow light dilemma,” the ambiguous situation where a driver should stop or proceed forward when unexpectedly faced with a yellow light. This situation is even further exacerbated by the tendency of aggressive drivers to inappropriately speed up on the yellow just to get through the traffic light. A survey of Canadian drivers conducted by the Traffic Injury Research Foundation found that 9% of drivers admitted to speeding up to get through a traffic light. Another reason for these accidents is the increased danger of making a left-hand turn on yellow. According to the National Highway Traffic Safety Association (NHTSA), left turns occur in approximately 22.2% of collisions—as opposed to just 1.2% for right turns. Moreover, a study by CNN found left turns are three times as likely to kill pedestrians than right turns. The reason left turns are so much more likely to cause an accident is because they take a driver against traffic and in the path of oncoming cars. Additionally, most of these left turns occur at the driver’s discretion—as opposed to the distressingly brief left-hand arrow at busy intersections. Drive Safe Now proposes a workable solution for reducing the number of accidents occurring during a yellow light at intersections. We believe this fairly simple solution will save lives, prevent injuries, reduce damage to public and private property, and decrease insurance costs. 展开更多
关键词 Traffic Accidents Yellow light Traffic light Signals INTERSECTION Crashes Collision Traffic Fatalities Traffic Injuries Vehicles SAFETY speed Limit Driving Pedestrians Bicyclists MOTORCYCLISTS Caution Line Yellow light Dilemma Left Hand Turn on Yellow Distance Smart Road Technology Signs Signage Autonomous Vehicles AVs Road Safety IoT Internet of Things Infrastructure Accident Reduction Driving Habits Stop Line Red light Jumping Pedestrian Safety Caution light Stopping at Intersection Safety at Intersections
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GE light speed 16排螺旋CT常见故障的维修和体会 被引量:9
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作者 苏根元 王萍萍 于小晶 《中国医学装备》 2011年第9期77-79,共3页
多排螺旋CT目前已广泛应用于临床,使用过程中会遇到各种各样故障,在熟练掌握多排螺旋CT的基本原理,工作结构,及相关计算机知识的基础上,可以对多排螺旋CT机很多常见故障进行快速及时修复,大大提高了设备使用率,保证临床工作的顺利进行... 多排螺旋CT目前已广泛应用于临床,使用过程中会遇到各种各样故障,在熟练掌握多排螺旋CT的基本原理,工作结构,及相关计算机知识的基础上,可以对多排螺旋CT机很多常见故障进行快速及时修复,大大提高了设备使用率,保证临床工作的顺利进行。本文简要阐述了我院GE light speed 16排螺旋CT在使用过程中常见的故障现象、诊断分析、解决方法和体会。为相关专业技术人员提供一定的参考和借鉴。 展开更多
关键词 GE light speed 16排螺旋CT 故障 维修 体会
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GE Light speed 16 CT在急腹症诊断中的应用 被引量:5
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作者 龙腾河 宾怀有 廖明壮 《医学信息(中旬刊)》 2010年第5期1315-1316,共2页
目的:探讨GE Light speed 16 CT在急腹症诊断中的应用价值。方法:回顾性分析318例接受个体化GE Light speed 16 CT扫描及三维重建的急腹症患者,所有患者经手术和临床治疗证实。结果:胃肠道穿孔55例;泌尿系结石76例;急性胆囊炎15例;胆总... 目的:探讨GE Light speed 16 CT在急腹症诊断中的应用价值。方法:回顾性分析318例接受个体化GE Light speed 16 CT扫描及三维重建的急腹症患者,所有患者经手术和临床治疗证实。结果:胃肠道穿孔55例;泌尿系结石76例;急性胆囊炎15例;胆总管结石30例;脾梗死3例;阑尾炎36例;憩室炎9例;小肠梗阻30例;主动脉夹层22例;急性胰腺炎15例。结论:GE Light speed 16 CT检查能应用于急腹症的诊断和鉴别。 展开更多
关键词 急腹症 GE light speed 16 CT 对比剂
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美国GE LightSpeed VCT故障维修一例
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作者 严劲 马靖武 《医疗装备》 2017年第9期65-66,共2页
1故障描述Light Speed VCT在使用过程中突然停止扫描,故障提示如下:Tue Jan 16 07:24:14 2016 Error:260133191orp orp_subsys filter.cxx 81Host:Collimator
关键词 light speed VCT 维修 滤线器 准直器
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GE light speed四层螺旋CT机图像伪影一例分析
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作者 宁殿秀 杜敏安 《医疗装备》 2004年第9期15-15,共1页
关键词 GE light speed四层螺旋CT机 图像伪影 故障 检查 维修
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GE Light speed 16 CT扫描技术在急腹症中的应用
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作者 龙腾河 《医疗卫生装备》 CAS 2009年第8期73-76,共4页
目的:探讨G ELight speed 16 CT扫描技术在急腹症中的应用。方法:系统总结各类急腹症所使用的GE Light speed 16 CT技术参数。结果:根据急腹症的病因和部位,选择合适的技术参数扫描可以快速、准确地诊断急腹症。结论:根据急腹症的个性应... 目的:探讨G ELight speed 16 CT扫描技术在急腹症中的应用。方法:系统总结各类急腹症所使用的GE Light speed 16 CT技术参数。结果:根据急腹症的病因和部位,选择合适的技术参数扫描可以快速、准确地诊断急腹症。结论:根据急腹症的个性应用GE Light speed 16 CT进行扫描,不但能快速提供急腹症影像资料和影像诊断,而且能够提高急腹症诊断的准确率。 展开更多
关键词 CT GElight speed 16CT 急腹症 对比剂
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A Topological Magueijo-Smolin Varying Speed of Light Theory, the Accelerated Cosmic Expansion and the Dark Energy of Pure Gravity 被引量:8
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作者 Mohamed Salah El Naschie Leila Marek-Crnjac +1 位作者 Mohamed Atef Helal Ji-Huan He 《Applied Mathematics》 2014年第12期1780-1790,共11页
The paper presents a detailed analysis of ordinary and dark energy density of the cosmos based on two different but complimentary theories. First, and starting from the concept of the speed of light being an average o... The paper presents a detailed analysis of ordinary and dark energy density of the cosmos based on two different but complimentary theories. First, and starting from the concept of the speed of light being an average over multi-fractals, we use Magueijo-Smolin’s ingenious revision of Einstein’s special relativity famous formula E = mc2 to a doubly special formula which includes the Planck energy as invariant to derive the ordinary energy density E(O) = mc2/22 and the dark energy density E(D) = mc2(21/22) wheremis the mass andcis the speed of light. Second we use the topological theory of pure gravity to reach the same result thus confirming the correctness of the theory of varying speed of light as well as the COBE, WMAP and Type 1a supernova cosmological measurements. 展开更多
关键词 Dark ENERGY QUANTUM GRAVITY VARYING speed of light THEORY ENERGY of QUANTUM Wave QUANTUM Non-Demolition
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Light-Speed LSX系统一次法和两次法治疗慢性根尖周炎的临床研究 被引量:2
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作者 吴志国 杜红保 +1 位作者 李斌 吴翠柳 《口腔医学》 CAS 2015年第10期864-866,共3页
目的采用Light-Speed LSX根管预备系统对慢性根尖周炎患者采用一次法根管治疗和两次法根管治疗,评估术后2年随访结果,比较二者治疗成功率。方法 300例上下颌慢性根尖周炎患牙随机分为2组,A组为一次性完成根管治疗,B组分次完成根管预备... 目的采用Light-Speed LSX根管预备系统对慢性根尖周炎患者采用一次法根管治疗和两次法根管治疗,评估术后2年随访结果,比较二者治疗成功率。方法 300例上下颌慢性根尖周炎患牙随机分为2组,A组为一次性完成根管治疗,B组分次完成根管预备和根管充填,所有组内患牙均使用Light-Speed LSX根管预备器械进行根管预备,评价患牙术后2年的临床和影像学表现。结果采用Light-Speed LSX根管预备系统进行根管预备,一次法组138例(93.88%)治愈,两次法组122例(89.05%)治愈;疗效不确定的一次法组5例(3.40%),两次法组9例(6.57%);治疗失败的一次法组4例(2.72%),两次法组6例(4.38%)。两组治疗成功率的比较采用卡方检验,结果显示两组治疗成功率无统计学差异(P>0.05)。结论采用Light-Speed LSX根管预备系统对慢性根尖周炎患者采用一次法根管治疗和两次法根管治疗成功率无差异。 展开更多
关键词 lightspeed LSX 根管治疗 慢性根尖周炎
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A New Discriminating Experiment on the Invariance Hypothesis of Light Speed 被引量:1
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作者 Jinxi Dong (Beijing Petrochemical College, Daxing, Beijing 102600, People’s Repulic of China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1995年第4期137-146,共10页
This thesis puts forward a conjecture that, owing to some unknown special character of light, it is impossible to determine whether the speed of light is variable by the interference method. To verify the hypothesis ... This thesis puts forward a conjecture that, owing to some unknown special character of light, it is impossible to determine whether the speed of light is variable by the interference method. To verify the hypothesis of the invariance of light speed, a new method must be found to take accurate measurement of the infinitesimal change in the travelling time of light. The thesis suggests the adoption of high frequency laser pulse technology to carry out the measurement. On the basis of this idea a new discriminating experiment is proposed to test the hypothesis of the invariance of light speed. The thesis also makes some forecast of the future prospects of this experiment and of the future development of the theory of special relativity. 展开更多
关键词 Invariance of the speed of light light pulse method CONJECTURE Discriminating experiment.
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A Probabilistic Method to Determine Whether the Speed of Light Is Constant 被引量:1
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作者 Motohisa Osaka 《Applied Mathematics》 2019年第2期51-59,共9页
Although the formula of mass-energy equivalence was derived from the hypothesis that the speed of light in free space is constant, conversely, the purpose of this research is to show that a method of probabilistically... Although the formula of mass-energy equivalence was derived from the hypothesis that the speed of light in free space is constant, conversely, the purpose of this research is to show that a method of probabilistically determining whether the speed of light is constant is derived from this formula. By considering the formula of mass-energy equivalence to be a function of the energy of an object moving at speed V, the probability density function (PDF) of the energy can be obtained using the inverse function of this formula, if the speed of light obeys a probability distribution. The main result is that the PDF of the energy diverges to infinity at a certain energy value regardless of the PDF of the speed of light. Thus, when the speed calculated from this value enters a certain range of the speed of light as V increases stepwise from below 299,792,458 m/s, the PDF of the energy should increase abruptly. If not, then the speed of light is constant. This is the method of probabilistically determining whether the speed of light is constant. An experimental method is proposed to confirm this. 展开更多
关键词 Special RELATIVITY light speed Mass-Energy EQUIVALENCE
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Extraction of the Speed of Gravity (Light) from Gravity Observations Only 被引量:1
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作者 Espen Gaarder Haug 《International Journal of Astronomy and Astrophysics》 2019年第2期97-114,共18页
We show how one can measure the speed of gravity only using gravitational phenomena. Our approach offers several ways to measure the speed of gravity (light) and checks existing assumptions about light (gravity) in ne... We show how one can measure the speed of gravity only using gravitational phenomena. Our approach offers several ways to measure the speed of gravity (light) and checks existing assumptions about light (gravity) in new types of experiments. The speed of light is included in several well-known gravitational formulas. However, if we can measure this speed from gravitational phenomena alone, then is it the speed of light or the speed of gravity we are measuring? We think it is more than a mere coincidence that they are the same. In addition, even if it is not possible to draw strong conclusions now, our formulations support the view that there is a link between electromagnetism and gravity. This paper also shows that all major gravity phenomena can be predicted from only performing two to three light observations. There is no need for knowledge of Newton’s gravitational constant G or the mass size to complete a series of major gravity predictions. 展开更多
关键词 speed of GRAVITY speed of light REDSHIFT Gravitational Time Dilation SCHWARZSCHILD Radius GRAVITY Predictions from light ONLY
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The Effect Density Has on the Speed of Light, Time, and the Dimensions of the Multiverse 被引量:1
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作者 Ardeshir Irani 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2022年第4期935-939,共5页
We show that as the dimensions of the Multiverse increase so does its density. This increase in density has the effect of decreasing the speed of light, slowing down time, and increasing the life span of each higher d... We show that as the dimensions of the Multiverse increase so does its density. This increase in density has the effect of decreasing the speed of light, slowing down time, and increasing the life span of each higher dimension and the life span of human beings occupying that higher dimension. We use the tenth dimension as the highest dimension as a special case but show that it is not possible to exactly determine its value because of varying factors that can end the Multiverse, sending all the Energy back into the original levels of the Quantum of the void that started the creation process. 展开更多
关键词 DENSITY GRAVITY TIME speed of light Higher Dimensions
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On the Possibility of Variable Speed of Light in Vacuum 被引量:1
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作者 Qinghua Cui 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2022年第4期927-934,共8页
We previously revealed a quantitative relation by which the fine-structure constant α can be described by the temperature T of cosmic microwave background (CMB) with several other fundamental constants, including the... We previously revealed a quantitative relation by which the fine-structure constant α can be described by the temperature T of cosmic microwave background (CMB) with several other fundamental constants, including the elementary charge e, the Boltzmann constant k, the Planck constant h, and the light of speed in vacuum c. Given that the value of α is quite conserved but T is variable across CMBs, we propose that c changes with T and can be given by T, the present CMB temperature T<sub>0</sub> and the present light speed c<sub>0</sub>. As T is continuously decreasing, c is thus predicted to decrease at a rate of ~2.15 centimeters/second (cm/s) per year. Moreover, we provide a lot of evidence to support this finding. In conclusion, this study suggests a possibility of variable speed of light in vacuum. 展开更多
关键词 speed of light in Vacuum Fine-Structure Constant Cosmic Microwave Background Earth-Moon Distance
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GE Light speed 4 CT后处理技术在结直肠癌诊断中的应用
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作者 韦林森 张克池 《医学信息(中旬刊)》 2011年第9期4409-4410,共2页
放射科结肠癌是消化道常见的恶性肿瘤之一,以男性发病率高,40~50岁为发病高峰年龄[1]。现对经手术或病理证实的结直肠癌30例的GE Light speed 4 CT的各种后处理技术在手术前诊断进行总结分析,并与病理结果对比分析。
关键词 GE light speed 4 CT 后处理技术 结直肠癌诊断 应用
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Star Mass Inertia Dictates the Speed of Light 被引量:1
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作者 Weihong Qian 《Journal of High Energy Physics, Gravitation and Cosmology》 2022年第1期184-194,共11页
This paper indicated that Newton’s law of gravitation is a statistical relation of two adjacent objects with a distance and Einstein’s general relativity shows the internal connection of material distribution throug... This paper indicated that Newton’s law of gravitation is a statistical relation of two adjacent objects with a distance and Einstein’s general relativity shows the internal connection of material distribution through space-time warping in our universe so general relativity is referred as a gravity theory. Here the paper gives an extension of general relativity in the sense of the metric theory of gravity which is consistent with Einstein’s equivalence principle and generates a weak field approximation which extends Newtonian dynamics. Thus, the extended theory of gravity can infer that the light has a speed limit of photon escaping the mass inertia of a star. 展开更多
关键词 NEWTON EINSTEIN Star Mass Inertia PHOTON Gravity the speed of light
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A Unified Newtonian-Relativistic Quantum Resolution of the Supposedly Missing Dark Energy of the Cosmos and the Constancy of the Speed of Light 被引量:3
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作者 M.S.El Naschie 《International Journal of Modern Nonlinear Theory and Application》 2013年第1期43-54,共12页
Time dilation, space contraction and relativistic mass are combined in a novel fashion using Newtonian dynamics. In this way we can surprisingly retrieve an effective quantum gravity energy-mass equation which gives t... Time dilation, space contraction and relativistic mass are combined in a novel fashion using Newtonian dynamics. In this way we can surprisingly retrieve an effective quantum gravity energy-mass equation which gives the accurate experimental value of vacuum density. Furthermore Einstein’s equation of special relativity E = mc2, where m is the mass and c is the velocity of light developed assuming smooth 4D space time is transferred to a rugged Calabi-Yau and K3 fuzzy Kahler manifolds and revised to become E=(mc2)/(22), where the division factor 22 maybe interpreted as the compactified bosonic dimensions of Veneziano-Nambu strings. The result is again an accurate effective quantum gravity energy-mass relation akin to the one found using Newtonian dynamics which correctly predicts that 95.4915028% of the energy in the cosmos is the hypothetical missing dark energy. The agreement with WMAP and supernova measurements is in that respect astounding. In addition different theories are used to check the calculations and all lead to the same quantitative result. Thus the theories of varying speed of light, scale relativity, E-infinity theory, M-theory, Heterotic super strings, quantum field in curved space time, Veneziano’s dual resonance model, Nash Euclidean embedding and super gravity all reinforce, without any reservation, the above mentioned theoretical result which in turn is in total agreement with the most sophisticated cosmological measurements which was deservingly awarded the 2011 Nobel Prize in Physics. Finally and more importantly from certain viewpoints, we reason that the speed of light is constant because it is a definite probabilistic expectation value of a variable velocity in a hierarchical fractal clopen, i.e. closed and open micro space time. 展开更多
关键词 Dark Energy Homology of Fuzzy Kahler Betti Numbers Heterotic Strings Revised Special Relativity speed of light as a Probabilistic Expectation Value
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Gravity Constraints on the Measurements of the Speed of Light 被引量:1
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作者 Faical Ramdani 《International Journal of Astronomy and Astrophysics》 2019年第3期265-273,共9页
The speed of light in a vacuum is a constant of special relativity, electromagnetic wave theories, and astrophysical distances. However, several measurements of its speed (c) at locations on the Earth’s surface seem ... The speed of light in a vacuum is a constant of special relativity, electromagnetic wave theories, and astrophysical distances. However, several measurements of its speed (c) at locations on the Earth’s surface seem to vary at different times during the last century. Efforts have been made on instruments performance to achieve a unique viable value in any spacetime referential. The time-variability on c-values obtained is here addressed inside the gravity field (g) in which the measurements of c have been estimated. It appears a correlation of c and g both daily (tidal) and yearly (no-tidal) variations which suggest that the gravity acceleration control the c-variability everywhere in a spacetime referential. Implications of this model provide a sensitivity constant of c from g, and the estimates of c on planets of the solar system where g values are known. It is deduced an upper limit of gravity in black hole that can cancel the speed of light in the horizon. 展开更多
关键词 GRAVITY TIME speed of light Solar System Black Hole
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