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On Some Mathematical Connections between the Cyclic Universe, Inflationary Universe, p-Adic Inflation, p-Adic Cosmology and Various Sectors of Number Theory
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作者 Michele Nardelli 《Journal of Modern Physics》 2024年第11期1869-1958,共90页
This paper is a review, a thesis, of some interesting results that have been obtained in various research concerning the “brane collisions in string and M-theory” (Cyclic Universe), p-adic inflation and p-adic cosmo... This paper is a review, a thesis, of some interesting results that have been obtained in various research concerning the “brane collisions in string and M-theory” (Cyclic Universe), p-adic inflation and p-adic cosmology. In Section 2, we have described some equations concerning cosmic evolution in a Cyclic Universe. In Section 3, we have described some equations concerning the cosmological perturbations in a Big Crunch/Big Bang space-time, the M-theory model of a Big Crunch/Big Bang transition and some equations concerning the solution of a braneworld Big Crunch/Big Bang Cosmology. In Section 4, we have described some equations concerning the generating ekpyrotic curvature perturbations before the Big Bang, some equations concerning the effective five-dimensional theory of the strongly coupled heterotic string as a gauged version of N=1five-dimensional supergravity with four-dimensional boundaries, and some equations concerning the colliding branes and the origin of the Hot Big Bang. In Section 5, we have described some equations regarding the “null energy condition” violation concerning the inflationary models and some equations concerning the evolution to a smooth universe in an ekpyrotic contracting phase with w>1. In Section 6, we have described some equations concerning the approximate inflationary solutions rolling away from the unstable maximum of p-adic string theory. In Section 7, we have described various equations concerning the p-adic minisuperspace model, zeta strings, zeta nonlocal scalar fields and p-adic and adelic quantum cosmology. In Section 8, we have shown various and interesting mathematical connections between some equations concerning the p-adic inflation, the p-adic quantum cosmology, the zeta strings and the brane collisions in string and M-theory. Furthermore, in each section, we have shown the mathematical connections with various sectors of Number Theory, principally the Ramanujan’s modular equations, the Aurea Ratio and the Fibonacci’s numbers. 展开更多
关键词 String theory m-theory Cyclic Cosmology p-Adic and Adelic Analysis Number theory Ramanujan’s modular Equations
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All the Fundamental Massless Fermion Fields in Superstring Theory: A Rigorous Analysis 被引量:1
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作者 Edward B. Manoukian 《Journal of Modern Physics》 2012年第9期1027-1030,共4页
A systematic rigorous analysis of both massless fermion fields in the mass spectra of superstring theory is carried out. Our interest is in dynamical aspects of these fields. An explicit novel expression for the propa... A systematic rigorous analysis of both massless fermion fields in the mass spectra of superstring theory is carried out. Our interest is in dynamical aspects of these fields. An explicit novel expression for the propagator of the massless Rarita-Schwinger field (the gravitino), in the mass spectrum involving massless fermions in superstring theory in 10 dimensions, is derived. The analysis is carried in the presence of a non-constrained external source so that the full expression of the propagator emerges. The number of associated degrees of freedom is also obtained. We work in a Coulomb-like gauge. The massless Dirac field (the dilatino), the other massless fermion field in the mass spectra of superstring theory in 10 dimensions, is first investigated to this end. 展开更多
关键词 mASSLESS FERmION FIELDS in superstring theory Rarita-Schwinger Field (the Gravitino) in 10 Dimensions Propagator theory
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基于M-DGM(1,1)模型的东江河流系统健康评估
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作者 方陈卓 王海鹏 +5 位作者 吴龙华 杨校礼 邓西平 武煜伦 张广明 李喜元 《水资源与水工程学报》 CSCD 北大核心 2024年第2期32-39,共8页
东江作为广东省和香港特别行政区的重要水源地,直接关系着珠三角地区的经济发展以及香港特区的繁荣稳定。为有效掌握东江河流系统健康状况的发展趋势,促进东江流域内经济社会的可持续发展,针对东江河流系统健康评分(2015—2019年)的振... 东江作为广东省和香港特别行政区的重要水源地,直接关系着珠三角地区的经济发展以及香港特区的繁荣稳定。为有效掌握东江河流系统健康状况的发展趋势,促进东江流域内经济社会的可持续发展,针对东江河流系统健康评分(2015—2019年)的振荡分布特性,基于灰色预测理论,结合等维灰数动态递补模型,构建了M-DGM(1,1)灰色预测模型,并利用该模型对东江河流系统(2020—2024年)的健康状况进行了评估。结果表明:该预测模型精度达到一级,可满足东江河流系统健康状况评估的要求;东江河流系统健康在2020—2024年间仍处于亚健康状态,但总体向着健康方向发展;部分敏感警兆指标评分(2020—2024年)发生波动,要继续加强对东江河流系统健康的保护与管理。 展开更多
关键词 河流系统健康 预测 灰色理论 m-DGm(1 1) 东江
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The Extremal Universe Exact Solution from Einstein’s Field Equation Gives the Cosmological Constant Directly
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作者 Espen Gaarder Haug 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期386-397,共12页
Einstein’s field equation is a highly general equation consisting of sixteen equations. However, the equation itself provides limited information about the universe unless it is solved with different boundary conditi... Einstein’s field equation is a highly general equation consisting of sixteen equations. However, the equation itself provides limited information about the universe unless it is solved with different boundary conditions. Multiple solutions have been utilized to predict cosmic scales, and among them, the Friedmann-Lemaître-Robertson-Walker solution that is the back-bone of the development into today standard model of modern cosmology: The Λ-CDM model. However, this is naturally not the only solution to Einstein’s field equation. We will investigate the extremal solutions of the Reissner-Nordström, Kerr, and Kerr-Newman metrics. Interestingly, in their extremal cases, these solutions yield identical predictions for horizons and escape velocity. These solutions can be employed to formulate a new cosmological model that resembles the Friedmann equation. However, a significant distinction arises in the extremal universe solution, which does not necessitate the ad hoc insertion of the cosmological constant;instead, it emerges naturally from the derivation itself. To the best of our knowledge, all other solutions relying on the cosmological constant do so by initially ad hoc inserting it into Einstein’s field equation. This clarification unveils the true nature of the cosmological constant, suggesting that it serves as a correction factor for strong gravitational fields, accurately predicting real-world cosmological phenomena only within the extremal solutions of the discussed metrics, all derived strictly from Einstein’s field equation. 展开更多
关键词 General Relativity theory Cosmological Constant Extremal Solution Reissner-Nordström KERR Kerr-Newman
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M⁃B模型弹塑性临界点确定方法
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作者 曹宏军 朱敏 +2 位作者 王盛凹 邓李重阳 马德胜 《机械强度》 CAS CSCD 北大核心 2024年第4期946-951,共6页
弹塑性临界点的确定对粗糙表面接触问题的研究至关重要。为了解决现有的M⁃B模型弹塑性临界点确定方法中,表征值不可测且难以应用的缺点,基于分形理论基本模型,运用数理统计得出了微凸体截断面积分布函数及概率分布密度。结合赫兹接触的... 弹塑性临界点的确定对粗糙表面接触问题的研究至关重要。为了解决现有的M⁃B模型弹塑性临界点确定方法中,表征值不可测且难以应用的缺点,基于分形理论基本模型,运用数理统计得出了微凸体截断面积分布函数及概率分布密度。结合赫兹接触的理想弹、塑性接触模型得出了具有分形特征的平面⁃平面接触过程中的法向力模型。基于塑性变形时的实际接触面积与截断面积的区别,提出了修正因子,最后得出以临界法向力为表征量的弹塑性临界点确定方法。新方法以法向力为表征量且需通过校准试验得出,更具操作性与可信度。 展开更多
关键词 m⁃B 模型 分形理论 弹塑性临界点 截断面积 法向力
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基于AHP-DEMATEL-ISM的煤矿安全投入结构研究
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作者 姜福川 王昊 +2 位作者 杨浩 明银龙 盛兵旺 《矿业安全与环保》 CAS 北大核心 2024年第4期90-95,共6页
为改善煤矿安全投入结构状况,更好地为煤矿安全生产服务,研究了煤矿安全投入结构影响因素的相互关系。采用m-IHEL理论分析煤矿企业安全结构,将其划分为人—机—环境—信息4个子系统,构建煤矿安全投入结构评价指标体系,并使用AHP-DEMATEL... 为改善煤矿安全投入结构状况,更好地为煤矿安全生产服务,研究了煤矿安全投入结构影响因素的相互关系。采用m-IHEL理论分析煤矿企业安全结构,将其划分为人—机—环境—信息4个子系统,构建煤矿安全投入结构评价指标体系,并使用AHP-DEMATEL-ISM模型进行分析评价。研究表明:安全教育培训、采掘安全设备、信息管理系统、安全监控系统是影响煤矿安全投入结构的关键因素,企业应该加强人员投入,重视环境和信息在煤矿系统的作用,以提高煤矿智能化水平。 展开更多
关键词 煤矿 安全投入 m-IHEL理论 AHP-DEmATEL-ISm 递阶结构
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The Correct Reissner-Nordstrøm, Kerr and Kerr-Newman Metrics
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作者 Carlo Maria Pace 《Journal of Modern Physics》 2024年第10期1502-1522,共21页
In a very recent article of mine I have corrected the traditional derivation of the Schwarzschild metric thus arriving to formulate a correct Schwarzschild metric different from the traditional Schwarzschild metric. I... In a very recent article of mine I have corrected the traditional derivation of the Schwarzschild metric thus arriving to formulate a correct Schwarzschild metric different from the traditional Schwarzschild metric. In this article, starting from this correct Schwarzschild metric, I also propose corrections to the other traditional Reissner-Nordstrøm, Kerr and Kerr-Newman metrics on the basis of the fact that these metrics should be equal to the correct Schwarzschild metric in the borderline case in which they reduce to the case described by this metric. In this way, we see that, like the correct Schwarzschild metric, also the correct Reissner-Nordstrøm, Kerr and Kerr-Newman metrics do not present any event horizon (and therefore do not present any black hole) unlike the traditional Reissner-Nordstrøm, Kerr and Kerr-Newman metrics. 展开更多
关键词 General theory of Relativity SCHWARZSCHILD Reissner-Nordstrøm KERR Kerr-Newman metric Event Horizon Black Hole
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六角GaM(M=S/Se/Te)的电子结构和力学性质的第一性原理计算
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作者 路羽茜 张鑫 李世娜 《功能材料》 CAS CSCD 北大核心 2024年第5期5134-5140,共7页
依据密度泛函理论(DFT)对层状六角P63/mmc结构的GaM(M=S/Se/Te)进行电子结构与弹性力学特性的模拟研究。优化后的P63/mmc-GaM(M=S/Se/Te)的晶格,与实验结果相吻合。采用HSE06泛函得到的带隙值比PBE得到的与实验值更接近。应变能-应变(E... 依据密度泛函理论(DFT)对层状六角P63/mmc结构的GaM(M=S/Se/Te)进行电子结构与弹性力学特性的模拟研究。优化后的P63/mmc-GaM(M=S/Se/Te)的晶格,与实验结果相吻合。采用HSE06泛函得到的带隙值比PBE得到的与实验值更接近。应变能-应变(E-S)和应力-应变(S-S)两种方法得到的P63/mmc-GaM(M=S/Se/Te)的单晶弹性常数都符合弹性力学稳定性准则。在更接近文献值的应力-应变(S-S)法基础上,对3种材料的多晶弹性模量等力学特性进行了后续分析。泊松比和B/G值表明,P63/mmc-GaM(M=S/Se/Te)显现出脆性。各向异性因子、杨氏模量E、剪切模量G及线性压缩系数β的三维立体图分别展示了材料的弹性各向异性程度。在零温零压下,P63/mmc-GaM(M=S/Se/Te)在[100]方向上的第一横向声速最大,在[001]方向上两个横波TA1和TA2的速度最慢。 展开更多
关键词 密度泛函理论 六角P63/mmc-Gam(m=S/Se/Te) 电子结构 力学性质 各向异性
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物流企业信息系统采纳因素研究--D&M模型与匹配理论的融合
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作者 向纯洁 曹子锐 《技术与创新管理》 2023年第6期679-688,744,共11页
随着信息化对企业带来竞争力的提升被广泛认可,物流企业也逐渐转向信息化发展模式,但物流企业信息化建设水平相对落后。为了解影响物流企业采纳信息系统的诸多因素,针对性地提高物流企业的信息系统采用率,运用结构方程模型,以D&M信... 随着信息化对企业带来竞争力的提升被广泛认可,物流企业也逐渐转向信息化发展模式,但物流企业信息化建设水平相对落后。为了解影响物流企业采纳信息系统的诸多因素,针对性地提高物流企业的信息系统采用率,运用结构方程模型,以D&M信息系统成功模型与匹配理论为研究框架,结合可供性理论和技术接受理论,从系统质量、信息质量和服务质量3个维度来分析物流企业信息系统使用的影响因素,以及对物流行业员工工作绩效的作用机制。研究表明:关联性、持续性、可见性、感知有用性、感知易用性对物流企业信息系统的采纳有正向影响,物流企业信息系统的采纳对物流企业绩效有正向影响。 展开更多
关键词 物流企业信息系统 D&m信息系统成功模型 匹配理论 可供性理论
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On a Fractal Version of Witten’s M-Theory 被引量:12
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作者 Mohamed S. El Naschie 《International Journal of Astronomy and Astrophysics》 2016年第2期135-144,共10页
Starting from Witten’s eleven dimensional M-theory, the present work develops in an analogous way a corresponding dimensional fractal version where . Subsequently, the new fractal formalism is utilized to determine t... Starting from Witten’s eleven dimensional M-theory, the present work develops in an analogous way a corresponding dimensional fractal version where . Subsequently, the new fractal formalism is utilized to determine the measured ordinary energy density of the cosmos which turns out to be intimately linked to the new theory’s fractal dimension via non-integer irrational Lorentzian-like factor: where is Hardy’s probability of quantum entanglement. Consequently, the energy density is found from a limiting classical kinetic energy to be Here, is ‘tHooft’s renormalon of dimensional regularization. The immediate logical, mathematical and physical implication of this result is that the dark energy density of the cosmos must be in astounding agreement with cosmic measurements and observations. 展开更多
关键词 m-theory E-Infinity theory Hardy’s Quantum Entanglement Transfinite Turing Computer Dark Energy Accelerated Cosmic Expansion Noncommutative Geometry superstring theory Scale Relativity Cantorian-Fractal Spacetime Witten’s theory ‘tHooft Renormalon Pure Gravity Penrose Tiling
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Analysis of Japan and World Records in the 100 m Dash Using Extreme Value Theory 被引量:2
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作者 Fumio Maruyama 《Journal of Applied Mathematics and Physics》 2021年第7期1442-1451,共10页
Extreme value theory provides methods to analyze the most extreme parts of data. We predicted the ultimate 100 m dash records for men and women for specific periods using the generalized extreme value (GEV) distributi... Extreme value theory provides methods to analyze the most extreme parts of data. We predicted the ultimate 100 m dash records for men and women for specific periods using the generalized extreme value (GEV) distribution. The various diagnostic plots, which assessed the accuracy of the GEV model, were well fitted to the 100 m records in the world and Japan, validating the model. The men’s world record had a shape parameter of -0.250 with a 95% confidence interval of [-0.391, -0.109]. The 100 m record had a finite limit and a calculated upper limit was 9.46 s. The return level estimates for the men’s world record were 9.74, 9.62, and 9.58 s with a 95% confidence interval of [9.69, 9.79], [9.54, 9.69], and [9.48, 9.67] for 10-, 100- and 350-year return periods, respectively. In one year, the probability of occurrence for a new world record of men, 9.58 s (Usain Bolt), was 1/350, while that for women, 10.49 s (Florence Griffith-Joyner), was about 1/100, confirming it was more difficult for men to break records than women. 展开更多
关键词 ATHLETICS 100 m Running Extreme Value theory GEV model
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A density functional theory structures, stabilities, and study on size-dependent electronic properties of bimetallic MnAgm (M=Na, Li; n + m ≤ 7) clusters
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作者 孙浩然 邝小渝 +2 位作者 李艳芳 邵鹏 赵亚儒 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第8期202-210,共9页
The equilibrium geometries, relative stabilities, and electronic properties of MnAgm(M=Na, Li; n + m ≤ 7) as well as pure Agn, Nan, Lin (n ≤ 7) clusters are systematically investigated by means of the density f... The equilibrium geometries, relative stabilities, and electronic properties of MnAgm(M=Na, Li; n + m ≤ 7) as well as pure Agn, Nan, Lin (n ≤ 7) clusters are systematically investigated by means of the density functional theory. The optimized geometries reveal that for 2 ≤ n ≤ 7, there are significant similarities in geometry among pure Agn, Nan, and Lin clusters, and the transitions from planar to three-dimensional configurations occur at n = 7, 7, and 6, respectively. In contrast, the first three-dimensional (3D) structures are observed at n + m = 5 for both NanAgm and LinAgm clusters. When n + m ≥5, a striking feature is that the trigonal bipyramid becomes the main subunit of LinAgm. Furthermore, dramatic odd-even alternative behaviours are obtained in the fragmentation energies, secondorder difference energies, highest occupied and lowest unoccupied molecular orbital energy gaps, and chemical hardness for both pure and doped clusters. The analytic results exhibit that clusters with an even electronic configuration (2, 4, 6) possess the weakest chemical reactivity and more enhanced stability. 展开更多
关键词 mnAgm m=Na Li) clusters density functional theory relative stability
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QED Cosmic Dark Energy Density Using Schwinger-Fredkin and E-Infinity Theory
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作者 Mohamed S. El Naschie 《Journal of Applied Mathematics and Physics》 2018年第4期621-627,共7页
The present paper utilizes the similarity between the non-perturbative Julian Schwinger-Efimov-Fredkin approach and that of E-infinity Cantorian spacetime theory to give an exact solution to the problem of cosmic dark... The present paper utilizes the similarity between the non-perturbative Julian Schwinger-Efimov-Fredkin approach and that of E-infinity Cantorian spacetime theory to give an exact solution to the problem of cosmic dark energy via a golden mean scaling-super quantization of the electromagnetic field. 展开更多
关键词 Schwinger-Fredkin method Super Quantization P-ADIC Expansion Electromagnetic Field The Standard model superstringS E-INFINITY theory
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Detailed analysis and simulation verification for reconstruction of plasma optical boundary with spectrometric technique on HL-2M tokamak 被引量:1
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作者 苏祉豪 高金明 高喆 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第7期25-34,共10页
The plasma optical boundary reconstruction technique based on Hommen's theory is promising for future tokamaks with high parameters. In this work, we conduct detailed analysis and simulation verification to estima... The plasma optical boundary reconstruction technique based on Hommen's theory is promising for future tokamaks with high parameters. In this work, we conduct detailed analysis and simulation verification to estimate the ‘logic loophole' of this technique. The finite-width effect and unpredictable errors reduce the technique's reliability, which leads to this loophole. Based on imaging theory, the photos of a virtual camera are simulated by integrating the assumed luminous intensity of plasma. Based on Hommen's theory, the plasma optical boundary is reconstructed from the photos. Comparing the reconstructed boundary with the one assumed, the logic loophole and its two effects are quantitatively estimated. The finite-width effect is related to the equivalent thickness of the luminous layer, which is generally about 2-4 cm but sometimes larger. The level of unpredictable errors is around 0.65 cm. The technique based on Hommen's theory is generally reliable, but finite-width effect and unpredictable errors have to be taken into consideration in some scenarios. The parameters of HL-2M are applied in this work. 展开更多
关键词 Hommen's theory simulation verification finite-width effect unpredictable errors spectrometric technique plasma boundary identification system HL-2m tokamak plasma boundary reconstruction
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Performance analysis of blockchain for civil aviation business data based on M/G/1 queuing theory
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作者 Liu Yiwei Zhang Yanhua +2 位作者 Yang Ruizhe Gao Yuan Zhang Xuanyi 《High Technology Letters》 EI CAS 2021年第4期388-396,共9页
An Ethereum blockchain based on proof of stake ( PoS) consensus mechanism is used to achieve the data sharing within the civil aviation service platform for both airport group management and passengers. Considering th... An Ethereum blockchain based on proof of stake ( PoS) consensus mechanism is used to achieve the data sharing within the civil aviation service platform for both airport group management and passengers. Considering the Gas consumption of Ethereum, the dynamic batch-service capacity constraint by the Block Gas Limit and the priority mechanism depending on the different Gas Price of transactions, M/ G/1 queuing theory with batch-service is used to construct the service model of transactions confirmation process in the proposed blockchain system, where the effects of transactions arrival rate, block capacity, service rate and number of nodes on the average confirmation time of transactions with different priority are analyzed, and eventually a performance analysis model of blockchain for civil aviation business data is proposed. The simulation results prove the usability and accuracy of the model, which can provide both theoretical basis for data sharing of civil aviation using Ethereum blockchain and the further optimization of transactions confirmation time. 展开更多
关键词 blockchain Ethereum proof of stake(PoS)consensus mechanism m/G/1 queuing theory PRIORITY
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Ultimate Olympics Records in Athletics Using Extreme Value Theory
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作者 Fumio Maruyama 《Open Journal of Applied Sciences》 2022年第4期541-554,共14页
Extreme value theory provides methods to analyze the most extreme parts of data. We used the generalized extreme value (GEV) distribution to predict the ultimate 100 m, 200 m, 400 m, 4 × 100 m relay, and long jum... Extreme value theory provides methods to analyze the most extreme parts of data. We used the generalized extreme value (GEV) distribution to predict the ultimate 100 m, 200 m, 400 m, 4 × 100 m relay, and long jump records of male gold medalists at the Olympics. The diagnostic plots, which assessed the accuracy of the GEV model, were fitted to all event records, validating the model. The 100 m, 200 m, 400 m, 4 × 100 m, and long jump records had negative shape parameters and calculated upper limits of 9.58 s, 19.18 s, 42.97 s, 36.71 s, and 9.03 m, respectively. The calculated upper limit in the 100 m (9.58 s) was equal to the record of Usain Bolt (August 16, 2009). The 100 m and 200 m world records were close to the calculated upper limits, and achieving the calculated limit was difficult. The 400 m and 4 × 100 m relay world records were almost equal to the calculated upper limits and the 500-year return level estimate, and slight improvement was possible in both. At the Tokyo Olympics in August 2021, in the 100 m, 200 m, and 4 × 100 m, in one year the probability of occurrence for a record was about 1/30. In the 400 m and long jump, it was about 1/20. In the 100 m, 200 m, and 4 × 100 m relay, more difficult records show that a fierce battle has taken place. 展开更多
关键词 ATHLETICS 100 m 200 m 400 m 4 × 100 m Relay Long Jump Extreme Value theory GEV model
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Electron Transfer Reaction between M-C_6H_6 and M^+-C_6H_6 Complexes in the Gas Phase: Density Functional Theory Study
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作者 Ai Ping FU, Dong Mei DU, Zheng Yu ZHOU (Department of Chemistry, Qufu Normal University,Shandong. Qufu 273165 State Key Laboratory Crystal Materials Shandong University, Shandong. Jinan 230100) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第3期219-222,共4页
DFT/BLYP method is used to theoretically investigate the electron transfer (ET) reactions between M (Li, Na, Mg)-C_6H_6 and M+-C_6H_6 complexes in the gas phase. The geometry optimization of the precursor complexes an... DFT/BLYP method is used to theoretically investigate the electron transfer (ET) reactions between M (Li, Na, Mg)-C_6H_6 and M+-C_6H_6 complexes in the gas phase. The geometry optimization of the precursor complexes and the transition state in the process of ET reaction was performed at 6-31G basis set level. The activation energy. the coupling matrix element and the rate constant of the ET reaction are calculated at semi-quantitative level. 展开更多
关键词 m-C_6H_6 complex density functional theory rate constant.
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The Efficient Market Theory and Mergers and Acquisitions (M&As) Puzzle: Evidence From Italy
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作者 Domenico Celenza Fabrizio Rossi 《Journal of Modern Accounting and Auditing》 2012年第11期1704-1711,共8页
The efficient market theory is a central point in finance. If the capital market is competitive, the investors cannot expect superior gains from their investment strategies with respect to the risk profile. Event stud... The efficient market theory is a central point in finance. If the capital market is competitive, the investors cannot expect superior gains from their investment strategies with respect to the risk profile. Event studies are an approach to verify the impact of the information on the stock prices. In an efficient market, stock prices should fully, promptly, and quickly capture all the information. Instead, the market shows phenomena of an under-reaction and over-reaction for both the short and the long run. The mergers and acquisitions (M&As) are examples of anomalies. Often, the bidder companies record the negative abnormal returns for both the short and the long run. In contrast to the efficient market theory, the empirical evidence shows that this phenomenon is widespread in all (or most of) the countries of the world. This work examines the long-run performance in M&As. For this purpose, 40 bidders were observed in Italy during the period of 1994-2008 among listed companies. The buy and hold abnormal returns (BHARs) methodology was used, with which it was possible to observe the returns for three years following the deal. 展开更多
关键词 efficient market theory mergers and acquisitions m&As) portfolio choice investment decisions buyand hold abnormal returns (BHARs) long-run performance Italian stock market
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Nash Embedding of Witten’s M-Theory and the Hawking-Hartle Quantum Wave of Dark Energy 被引量:2
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作者 Mohamed S. El Naschie 《Journal of Modern Physics》 2013年第10期1417-1428,共12页
Euclidean embedding of the 11-dimensional M-theory turned out to require a very large space leaving lavish amounts of 242 dimensional pseudo truly empty “regions” devoid of space and time and consequently of anythin... Euclidean embedding of the 11-dimensional M-theory turned out to require a very large space leaving lavish amounts of 242 dimensional pseudo truly empty “regions” devoid of space and time and consequently of anything resembling ordinary physical energy density. It is shown here using Nash embedding that the ratio of “solid” M-theory spacetime to its required embedding “non-spacetime” is 1/22 for a classical theory and 1/22.18033989 for an analogous fractal theory. This then leads to a maximal ordinary energy density equation equal to that of Einstein’s famous formula E=mc2 but multiplied with in full agreement with previous results obtained using relatively more conventional methods including running the electromagnetic fine structure constant in the exact solution of the hydrogen atom. Consequently, the new equation corresponds to a quantum relativity theory which unlike Einstein’s original equation gives quantitative predictions which agree perfectly with the cosmological measurements of WMAP and the analysis of certain supernova events. Never the less in our view dark energy also exists being the energy of the quantum wave amounting to 95.5 present of the total Einstein theoretical energy which is blind to any distinction between ordinary energy of the quantum particle and the dark energy of the quantum wave. However, since measurement leads to the collapse of the Hawking-Hartle quantum wave, dark energy being a quantum wave non-ordinary energy could not possibly be measured in the usual way unless highly refined quantum wave non-demolition technology is developed if possible. It is a further reason that dark energy having a different sign to ordinary energy is the cause behind the anti gravity force which is pushing the universe apart and accelerating cosmic expansion. Consequently it can be seen as the result of anticlastic Cartan-like curvature caused by extra compactified dimensions of spacetime. A simple toy model demonstration of the effect of curvature in a “material” space is briefly discussed. 展开更多
关键词 NASH Euclidean EmBEDDING QUANTUm Entanglement Dark ENERGY of the QUANTUm WAVE QUANTUm Gravity Ordinary ENERGY of the QUANTUm Particle Hawking-Hartle WAVE of the Cosmos QUANTUm WAVE Non-Demolition Witten’s m-theory
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On Supersymmetry of the Covariant 3-Algebra Model for M-Theory
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作者 Matsuo Sato 《Journal of Modern Physics》 2012年第11期1813-1818,共6页
We examine a natural supersymmetric extension of the bosonic covariant 3-algebra model for M-theory proposed in [1]. It possesses manifest SO(1,10) symmetry and is constructed based on the Lorentzian Lie 3-algebra ass... We examine a natural supersymmetric extension of the bosonic covariant 3-algebra model for M-theory proposed in [1]. It possesses manifest SO(1,10) symmetry and is constructed based on the Lorentzian Lie 3-algebra associated with the U(N) Lie algebra. There is no ghost related to the Lorentzian signature in this model. It is invariant under 64 supersymmetry transformations although the supersymmetry algebra does not close. From the model, we derive the BFSS matrix theory and the IIB matrix model in a large N limit by taking appropriate vacua. 展开更多
关键词 m-theory 3-Algebra matrix mODEL STRING theory
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