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Four-Dimensional Mathematics Creates the Super Universe
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作者 Ahti Rahikainen 《World Journal of Mechanics》 2023年第7期135-148,共14页
In the common theory of the Universe, the redshift of the light wavelength from distant stars indicates the speed of the star. In this study, the model of the Universe is the surface volume of the four-dimensional sph... In the common theory of the Universe, the redshift of the light wavelength from distant stars indicates the speed of the star. In this study, the model of the Universe is the surface volume of the four-dimensional sphere, and the shape of the Universe results in the most of the redshift of light wavelength. Therefore, there is no dark energy accelerating the Universe. The surface of the four-dimensional sphere is a volume, and this volume is a good model for the Universe. The surface volume of the four-dimensional sphere has been explained by a model of four-dimensional cube, within which the forming of surface volume can be easily shown. The model of four-dimensional cube containing six side cubes is ingenious for explaining the structure of the four-dimensional Universe, but it is not enough because the four-dimensional cube has not six side cubes, but eight side cubes. Therefore, in this study a better method has been created to construct the four-dimensional cube. Our three-dimensional Universe is the surface of the four-dimensional sphere Universe. The volume of our three-dimensional Universe is finite, and beneath it is the infinite volume four-dimensional Super Universe. Two important basic formulae have been derived: The surface volume of the four-dimensional sphere is π<sup>3</sup>R<sup>3</sup> in which R is the radius of the sphere, and the fourth-power volume of the four-dimensional sphere is 1/4 π<sup>3</sup>R<sup>4</sup>. The volume of the Universe has been calculated π<sup>3</sup>R<sup>3</sup> = 62 × 10<sup>30</sup> ly<sup>3</sup>. Time as the fourth dimension of the space takes effect only near the speed of light, and therefore it has been ignored in this study. 展开更多
关键词 Mathematics of the four-dimensional space Structure of the Universe Dark Matter Dark Energy Expansion of the Universe Big Bang four-dimensional Sphere four-dimensional Matter Atom Theory
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Study on eigenvalue space of hyperchaotic canonical four-dimensional Chua's circuit
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作者 李冠林 陈希有 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第3期137-144,共8页
The eigenvalue space of the canonical four-dimensional Chua's circuit which can realize every eigenvalue for fourdimensional system is studied in this paper. First, the analytical relations between the circuit parame... The eigenvalue space of the canonical four-dimensional Chua's circuit which can realize every eigenvalue for fourdimensional system is studied in this paper. First, the analytical relations between the circuit parameters and the eigenvalues of the system are established, and therefore all the circuit parameters can be determined explicitly by any given set of eigenvalues. Then, the eigenvalue space of the circuit is investigated in two cases by the nonlinear elements used. According to the types of the eigenvalues, some novel hyperchaotic attractors are presented. Further, the dynamic behaviours of the circuit are studied by the bifurcation diagrams and the Lyapunov spectra of the eigenvalues. 展开更多
关键词 four-dimensional Chua's circuit eigenvalue space HYPERCHAOS
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Study and application of an improved four-dimensional variational assimilation system based on the physical-space statistical analysis for the South China Sea
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作者 Yumin Chen Jie Xiang +2 位作者 Huadong Du Sixun Huang Qingtao Song 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第1期135-146,共12页
The four-dimensional variational assimilation(4D-Var)has been widely used in meteorological and oceanographic data assimilation.This method is usually implemented in the model space,known as primal approach(P4D-Var).A... The four-dimensional variational assimilation(4D-Var)has been widely used in meteorological and oceanographic data assimilation.This method is usually implemented in the model space,known as primal approach(P4D-Var).Alternatively,physical space analysis system(4D-PSAS)is proposed to reduce the computation cost,in which the 4D-Var problem is solved in physical space(i.e.,observation space).In this study,the conjugate gradient(CG)algorithm,implemented in the 4D-PSAS system is evaluated and it is found that the non-monotonic change of the gradient norm of 4D-PSAS cost function causes artificial oscillations of cost function in the iteration process.The reason of non-monotonic variation of gradient norm in 4D-PSAS is then analyzed.In order to overcome the non-monotonic variation of gradient norm,a new algorithm,Minimum Residual(MINRES)algorithm,is implemented in the process of assimilation iteration in this study.Our experimental results show that the improved 4D-PSAS with the MINRES algorithm guarantees the monotonic reduction of gradient norm of cost function,greatly improves the convergence properties of 4D-PSAS as well,and significantly restrains the numerical noises associated with the traditional 4D-PSAS system. 展开更多
关键词 four-dimensional variational data assimilation(4D-Var) physical space analysis system(PSAS) conjugate gradient algorithm(CG) minimal residual algorithm(MINRES) South China Sea
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Modified Lorentz Transformations and Space-Time Splitting According to the Inverse Relativity Model
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作者 Michael Girgis 《Journal of Applied Mathematics and Physics》 2024年第7期2467-2489,共23页
Analysis of a four-dimensional displacement vector on the fabric of space-time in the special or general case into two Four-dimensional vectors, according to specific conditions leads to the splitting of the total fab... Analysis of a four-dimensional displacement vector on the fabric of space-time in the special or general case into two Four-dimensional vectors, according to specific conditions leads to the splitting of the total fabric of space-time into a positive subspace-time that represents the space of causality and a negative subspace-time which represents a space without causality, thus, in the special case, we have new transformations for the coordinates of space and time modified from Lorentz transformations specific to each subspace, where the contraction of length disappears and the speed of light is no longer a universal constant. In the general case, we have new types of matric tensor, one for positive subspace-time and the other for negative subspace-time. We also find that the speed of the photon decreases in positive subspace-time until it reaches zero and increases in negative subspace-time until it reaches the speed of light when the photon reaches the Schwarzschild radius. 展开更多
关键词 four-dimensional Vector Analysis four-dimensional Subspace Causal space Analysis of the Speed of Light Inverse Theory of Relativity
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RELAXED ELASTIC LINES OF SECOND KIND ON ORIENTED SURFACE IN MINKOWSKI SPACE 被引量:1
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作者 Ayhan TUTAR Ayhan SARIO■LUG■L 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第11期1481-1489,共9页
The relaxed elastic line of second kind on an oriented surface in the Minkowski space was defined and for the relaxed elastic line of second kind which is lying on an oriented surface the Euler-Lagrange equations were... The relaxed elastic line of second kind on an oriented surface in the Minkowski space was defined and for the relaxed elastic line of second kind which is lying on an oriented surface the Euler-Lagrange equations were derived. Furthermore, whether these curves lie on a curvature line or not was investigated and some applications were given. 展开更多
关键词 elastic line GEODESIC minkowski space Euler-Lagrange equations
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Elastic Collisions in Minkowski Momentum Space with Lorentz Transformations 被引量:1
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作者 Akihiro Ogura 《World Journal of Mechanics》 2019年第12期267-284,共18页
We reexamined the elastic collision problems in the special relativity for both one and two dimensions from a different point of view. In order to obtain the final states in the laboratory system of the collision prob... We reexamined the elastic collision problems in the special relativity for both one and two dimensions from a different point of view. In order to obtain the final states in the laboratory system of the collision problems, almost all textbooks in the special relativity calculated the simultaneous equations. In contrast to this, we make a detour through the center-of-mass system. The two frames of references are connected by the Lorentz transformation with the velocity of the center-of-mass. This route for obtaining the final states is easy for students to understand the collision problems. For one dimensional case, we also give an example for illustrating the states of the particles in the Minkowski momentum space, which shows the whole story of the collision. 展开更多
关键词 RELATIVISTIC ELASTIC COLLISION minkowski MOMENTUM space LORENTZ Transformation
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On the Geometry of Curves in Minkowski 3-Space and Its Foldings
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作者 A. E. El-Ahmady E. Al-Hesiny 《Applied Mathematics》 2013年第5期746-752,共7页
We will introduce a new connection between some transformations and some aspects of differential geometry of some curves in Minkowski space. The concept of folding, retractions and contraction on some curves in Minkow... We will introduce a new connection between some transformations and some aspects of differential geometry of some curves in Minkowski space. The concept of folding, retractions and contraction on some curves in Minkowski space will be characterized by using some aspects of differential geometry. Types of the deformation retracts of some curves in Minkowski 3-space are obtained. The relations between the foldings and the deformation retracts of some curves are deduced. The connections between some transformations and time like, space like, light like of some curves in Minkowski 3-space are also presented. 展开更多
关键词 RETRACTIONS Deformation Retracts FOLDING CONTRACTION minkowski 3-space
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Group Inverse of 2 × 2 Block Matrices over Minkowski Space M
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作者 Dandapany Krishnaswamy Tasaduq Hussain Khan 《Advances in Linear Algebra & Matrix Theory》 2016年第3期75-87,共13页
Necessary and sufficient conditions for the existence of the group inverse of the block matrix in Minkowski Space are studied, where are both square and . The representation of this group inverse and some related addi... Necessary and sufficient conditions for the existence of the group inverse of the block matrix in Minkowski Space are studied, where are both square and . The representation of this group inverse and some related additive results are also given. 展开更多
关键词 Block Matrix Group Inverse minkowski Adjoint minkowski space
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Light and Entanglement Velocities for the Electron and the Proton in Minkowskian Space Require Surface Areas that Approximate the Human Cerebrum: Implications for Excess Correlations
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作者 Michael A. Persinger Nicolas Rouleau 《Journal of Quantum Information Science》 2016年第2期98-104,共8页
The distinctions between locality and non-locality as well as causality and excess correlation may be related to coupling between increments of space-time or to the total space-time within the universe as a unit. The ... The distinctions between locality and non-locality as well as causality and excess correlation may be related to coupling between increments of space-time or to the total space-time within the universe as a unit. The most likely candidates for the latter are the proton and the electron when related by Minkowski’s space-time. When two velocities: light in a vacuum for locality and the “entanglement” velocity based upon parameters that define the universe for non-locality, are considered the two times required to produce identities for the -v<sup>2</sup>t<sup>2</sup> components are frequencies whose energies approximate the neutral hydrogen line (primarily associated with shifts in electron spin direction) and the mass equivalence of a proton. The values for the additional three spatial dimensions required to produce a solution whose square root is not imaginary and greater than zero are within the domains of the surface areas of the human cerebrum. Detailed calculations converge to show that the proportions of energy that represent the electron’s Compton energy and the proton’s mass equivalent may be central to the condition of excess correlation within the cerebral volume. Proton channels within the neuronal cell plasma membranes whose pH-dependent specific currents produce the required magnetic field strengths could be the physical substrates by which excess correlations between brain activities of human subjects separated by non-local distances might occur. If protons are considered as the basic Eddington (number) units of the universe then Mach’s principle that any component of the universe is determined by all of its components may be testable empirically. 展开更多
关键词 Excess Correlation ENTANGLEMENT Proton Channels Neutral Hydrogen Wavelength minkowski space Causality’ Non-Locality
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n维空间中Minkowski差的性质
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作者 吴焕春 贾翔宇 +1 位作者 董保珠 孙翠先 《唐山师范学院学报》 2023年第3期3-4,共2页
研究了n维实空间中集族的Minkowski差的性质,给出了一些重要的计算方法,探讨了Minkowski差的应用。
关键词 实空间 minkowski 代数差
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四维Minkowski空间中伪零曲线的伴随曲线
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作者 张佳欣 胡娜 姜杨 《高师理科学刊》 2023年第7期18-21,共4页
定义了四维Minkowski空间中伪零曲线的伴随曲线.利用伪零曲线的特殊性,将欧氏空间中曲线的性质扩展到伪欧氏空间.通过对伪零曲线及其伴随曲线的Frenet标架的讨论,给出不同类型伴随曲线的曲率函数表达方式.讨论了特殊曲线的伴随曲线的曲... 定义了四维Minkowski空间中伪零曲线的伴随曲线.利用伪零曲线的特殊性,将欧氏空间中曲线的性质扩展到伪欧氏空间.通过对伪零曲线及其伴随曲线的Frenet标架的讨论,给出不同类型伴随曲线的曲率函数表达方式.讨论了特殊曲线的伴随曲线的曲率函数,并给出相应实例. 展开更多
关键词 minkowski空间 伪零曲线 伴随曲线 Frenet标架 积分曲线 曲率函数
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三维Minkowski空间内的空间型曲线 被引量:8
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作者 裴东河 孙伟志 +1 位作者 帕提古丽 张立新 《东北师大学报(自然科学版)》 CAS CSCD 北大核心 2004年第3期1-9,共9页
 应用奇点理论方法对三维Minkowski空间内由空间型曲线生成的副法线标型和可展焦曲面的奇点进行了分类,并且研究了在Lorenzian群作用下的空间型曲线的几何学不变量同这些奇点之间的关系.
关键词 三维minkowski空间 空间型曲线 奇点
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三维Minkowski空间内的时间型曲线 被引量:6
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作者 裴东河 孙伟志 金应龙 《东北师大学报(自然科学版)》 CAS CSCD 北大核心 2001年第3期25-33,共9页
定义了三维Minkowski空间内的时间型曲线的副法线标型和可展焦面 ,并对它们奇点分类进行了研究 。
关键词 三维minkowski空间 时间型曲线 奇点
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三维Minkowski空间中的平移曲面 被引量:2
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作者 袁媛 张金亮 +1 位作者 李春秀 刘会立 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第2期302-304,共3页
在三维Minkowski空间中,存在类空、类时和类光三种向量,选取这三种向量中的任意两种作为两个平移方向,可以将平移曲面分为六类.在伪正交标架下,选取一种新的度量形式,对沿两个类光方向平移的平移Weingarten曲面进行了研究.首先,根据微... 在三维Minkowski空间中,存在类空、类时和类光三种向量,选取这三种向量中的任意两种作为两个平移方向,可以将平移曲面分为六类.在伪正交标架下,选取一种新的度量形式,对沿两个类光方向平移的平移Weingarten曲面进行了研究.首先,根据微分几何中的基本知识,得到了该种度量形式下的平移曲面的第一、第二基本形式以及高斯曲率和平均曲率;然后,主要利用高斯曲率和平均曲率之间的线性关系和平方关系,得到了这类平移曲面的分类定理. 展开更多
关键词 minkowski空间 平移曲面 WEINGARTEN曲面 伪正交标架
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空间型M^(n+1)(a)中的Minkowski公式 被引量:3
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作者 王幼宁 苏效乐 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第5期602-606,共5页
把 R3 中二维闭曲面的
关键词 闭曲面 空间型 minkowski公式 截面曲率 RIEMANN流形 超曲面
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三维Minkowski空间中的伪球面曲线 被引量:2
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作者 于延华 刘会立 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2007年第6期902-904,共3页
在三维Minkowski空间中讨论伪球面曲线.首先给出Minkowski空间中伪球面曲线的Frenet标架,然后利用伪球面曲线的特殊性,给出它的一种新的Frenet标架形式,并进一步研究了该曲线为一些特殊曲线的情况.
关键词 不定度量 minkowski空间 DE SITTER空间 贝特朗曲线 曼哈姆曲线
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网格环境下剖分算法提高Minkowski求和效率的实验研究 被引量:1
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作者 马绍惠 卓伟 王志华 《科学技术与工程》 北大核心 2014年第3期204-207,共4页
Minkowski和的边界值是实现位置空间障碍物的关键技术,为改进算法的运行和求和速度,采用凹多面体回路的近似精确算法设计。首先指出了传统多面体算法的不足,进行完成了改进算法的设计及分析。实验验证采用了凸四面体、凹九面体顶点坐标... Minkowski和的边界值是实现位置空间障碍物的关键技术,为改进算法的运行和求和速度,采用凹多面体回路的近似精确算法设计。首先指出了传统多面体算法的不足,进行完成了改进算法的设计及分析。实验验证采用了凸四面体、凹九面体顶点坐标,在给出了详细的实验过程后得出:相比旧算法设计的改进算法执行时间较短,未出现新的顶点,实现了凹多面体的近似精确Minkowski和多面体边界表示,执行时间对比进一步验证了效率的改进。这一研究对于三维虚拟实验室和三维模型数据传输技术的改进具有一定的意义。 展开更多
关键词 minkowski空间 凹面体 精确算法 虚拟实验室
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三维Minkowski空间中的k-型伪零螺线 被引量:2
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作者 钱金花 刘杰 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2020年第6期909-912,共4页
在三维Minkowski空间中定义k-型伪零螺线,并结合结构函数讨论k-型伪零螺线的几何性质.首先,根据伪零曲线的概念定义伪零曲线的结构函数,进而得到伪零曲线的结构表达式以及结构函数与伪零曲线的曲率函数之间满足的关系.然后,讨论k-型伪... 在三维Minkowski空间中定义k-型伪零螺线,并结合结构函数讨论k-型伪零螺线的几何性质.首先,根据伪零曲线的概念定义伪零曲线的结构函数,进而得到伪零曲线的结构表达式以及结构函数与伪零曲线的曲率函数之间满足的关系.然后,讨论k-型伪零螺线的几何性质.结果表明,三维Minkowski空间中任意伪零曲线都是1-型伪零螺线,不存在2-型伪零螺线以及得到了3-型伪零螺线的曲率函数满足的微分方程等结论.与此同时,给出k-型伪零螺线的轴的表达式以及轴的类型(类空轴、类时轴、类光轴). 展开更多
关键词 minkowski空间 伪零曲线 k-型伪零螺线 结构函数 曲率
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Clifford代数与Minkowski空间的性质 被引量:27
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作者 李武明 《吉林大学自然科学学报》 CSCD 2000年第4期13-16,共4页
以 Clifford代数为工具 ,讨论 Minkowski空间的几何性质及狭义相对论的空时结构 ,指明应用
关键词 CLIFFORD代数 狭义相对论 空时结构
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三维Minkowski空间中的平移曲面 被引量:1
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作者 袁媛 刘会立 《沈阳师范大学学报(自然科学版)》 CAS 2015年第3期396-399,共4页
讨论三维Minkowski空间中的平移曲面。曲面的性质主要取决于高斯曲率和平均曲率,所以研究曲面的高斯曲率和平均曲率之间的关系,也就是曲面的Weingarten型有着重要的意义。在三维Minkowski空间中,存在类空、类时、和类光3种向量,选取这3... 讨论三维Minkowski空间中的平移曲面。曲面的性质主要取决于高斯曲率和平均曲率,所以研究曲面的高斯曲率和平均曲率之间的关系,也就是曲面的Weingarten型有着重要的意义。在三维Minkowski空间中,存在类空、类时、和类光3种向量,选取这3种向量中的任意2种作为2个平移方向,可以将平移曲面分为6类。在伪正交标架下,选取一种新的度量形式,对沿类光和类空方向平移的平移Weingarten曲面进行了研究。首先,根据微分几何中的基本知识,得到了该种度量形式下的平移曲面的第1、第2基本形式以及高斯曲率和平均曲率;然后,主要利用高斯曲率和平均曲率之间的线性关系和平方关系,得到了这类平移曲面的分类定理。 展开更多
关键词 minkowski空间 平移曲面 WEINGARTEN曲面 伪正交标架
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