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Gravitational Collapse and Expansion in the Newton Theory and General Relativity
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作者 Valery V. Vasiliev Leonid V. Fedorov 《Journal of Modern Physics》 2025年第2期294-309,共16页
The paper is devoted to the study of the gravitational collapse within the framework of the spherically symmetric problem in the Newton theory and general relativity on the basis of the pressure-free model of the cont... The paper is devoted to the study of the gravitational collapse within the framework of the spherically symmetric problem in the Newton theory and general relativity on the basis of the pressure-free model of the continuum. In application to the Newton gravitation theory, the analysis consists of three stages. First, we assume that the gravitational force is determined by the initial sphere radius and constant density and does not change in the process of the sphere collapse. The obtained analytical solution allows us to find the collapse time in the first approximation. Second, we construct the step-by-step process in which the gravitational force at a given time moment depends on the current sphere radius and density. The obtained numerical solution specifies the collapse time depending on the number of steps. Third, we find the exact value of the collapse time which is the limit of the step-by-step solutions and study the collapse and the expansion processes in the Newton theory. In application to general relativity, we use the space model corresponding to the special four-dimensional space which is Euclidean with respect to space coordinates and Riemannian with respect to the time coordinate only. The obtained solution specifies two possible scenarios. First, sphere contraction results in the infinitely high density with the finite collapse time, which does not coincide with the conventional result corresponding to the Schwarzschild geometry. Second, sphere expansion with the velocity which increases with a distance from the sphere center and decreases with time. 展开更多
关键词 Gravitational Collapse Newton Gravitation Theory General relativity
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Study on association rules mining based on semantic relativity 被引量:2
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作者 张磊 夏士雄 +1 位作者 周勇 夏战国 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期358-360,共3页
An association rules mining method based on semantic relativity is proposed to solve the problem that there are more candidate item sets and higher time complexity in traditional association rules mining.Semantic rela... An association rules mining method based on semantic relativity is proposed to solve the problem that there are more candidate item sets and higher time complexity in traditional association rules mining.Semantic relativity of ontology concepts is used to describe complicated relationships of domains in the method.Candidate item sets with less semantic relativity are filtered to reduce the number of candidate item sets in association rules mining.An ontology hierarchy relationship is regarded as a directed acyclic graph rather than a hierarchy tree in the semantic relativity computation.Not only direct hierarchy relationships,but also non-direct hierarchy relationships and other typical semantic relationships are taken into account.Experimental results show that the proposed method can reduce the number of candidate item sets effectively and improve the efficiency of association rules mining. 展开更多
关键词 ONTOLOGY association rules mining semantic relativity
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Lorentz Transformation Derived from Relativity of Time
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作者 Jianzhong Zhao 《Journal of Modern Physics》 2022年第6期851-857,共7页
The principles of special relativity and Einstein’s simple derivation of the Lorentz transformation are reviewed. A new simple derivation of the Lorentz transformation is developed in this paper, by a new approach of... The principles of special relativity and Einstein’s simple derivation of the Lorentz transformation are reviewed. A new simple derivation of the Lorentz transformation is developed in this paper, by a new approach of light-pulse observation or time-dilation observation. Therefore, under the two principles of special relativity, there exist two equivalent simple derivations of or two equivalent approaches to the Lorentz transformation. Einstein’s approach emphasizes or highlights relativity of space while our approach emphasizes or highlights relativity of time. This research reveals, in a particular way, the equivalence of relativity of space and relativity of time in special relativity. Combination of Einstein’s approach and the approach developed in this paper makes the methodology of simple derivation of the Lorentz transformation complete and perfect. 展开更多
关键词 Special relativity Lorentz Transformation relativity of Space relativity of Time
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From De Sitter Special Relativity and Snyder's Model to Complete Yang Model
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作者 于玥 吴宏途 郭汉英 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第11期819-824,共6页
The de Sitter special relativity on the Beltrami-de Sitter-spacetime and Snyder's model in the momentum space can be combined together with an IR-UV duality to get the complete Yang model at both classical and quantu... The de Sitter special relativity on the Beltrami-de Sitter-spacetime and Snyder's model in the momentum space can be combined together with an IR-UV duality to get the complete Yang model at both classical and quantum levels, which are related by the proposed Killing quantization. It is actually a special relativity based on the principle of relativity of three universal constants (c, ρp, R). 展开更多
关键词 principle of relativity de Sitter special relativity Snyder's model complete Yang model
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Relativity Isoframes—A Useful and Potentially Unifying Conceptual Framework
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2021年第6期731-738,共8页
This brief note introduces the conceptual framework of special and general relativity isoclocks and isoframes. Isoclocks and isoframes, as defined herein, can be used to create geometrical maps of space and time (“sp... This brief note introduces the conceptual framework of special and general relativity isoclocks and isoframes. Isoclocks and isoframes, as defined herein, can be used to create geometrical maps of space and time (“space-time”) with and without matter embedded. They are useful for having a mental picture of space-time relationships without having to picture 4-dimensional manifolds, which very few students and scientists are able to do. With the aid of the optical lensing definition of curvature as inverse radius, a new gravitational force equation is derived, which also incorporates Einstein’s mass/energy relation in the <em>m</em><sub><em>x</em></sub> term. Thus, one may see how it is that gravitational force correlates with its time-embedded curvature-squared (<span style="white-space:nowrap;"><em>C</em><sub><em>x</em></sub><sup style="margin-left:-7px;"><em>2</em></sup></span>) space in a more accurate formulation than could be envisioned by Newton. This becomes more apparent in high gamma fields, such as found near a black hole horizon. It is hoped that probability theories, such as quantum field theories in curved space-time, might be adaptable to the general relativity isoframe concept introduced herein. 展开更多
关键词 Isoframe Isoclock General relativity Special relativity SPACE-TIME Black Holes Krogdahl Unification
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An Analysis of Students' Mistakes through Linguistic Relativity
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作者 赵瑶 《海外英语》 2013年第17期116-117,共2页
Sapir-Whorf Hypothesis is controversial, but the Linguistic Relativity is universally accepted by scholars. Through ana lyzing the causes of the mistakes that students often make during English learning and the relati... Sapir-Whorf Hypothesis is controversial, but the Linguistic Relativity is universally accepted by scholars. Through ana lyzing the causes of the mistakes that students often make during English learning and the relationship among thoughts, cultures and languages, this paper argues that language can influence people's thoughts and people's thoughts can influence the acquisi tion of a second language. 展开更多
关键词 LINGUISTIC relativity THOUGHTS CULTURES LANGUAGES
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GPS Satellite Clock Corrections without Relativity Theory
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作者 Stephan J. G. Gift 《Journal of Applied Mathematics and Physics》 2021年第10期2476-2482,共7页
The GPS satellite clock corrections (along with gravitational redshift) which are necessary for the proper operation of the GPS are fully described without invoking relativity theory as is the practice today.
关键词 GPS Selleri Transformations Time Dilation Gravitational Time Dilation Special relativity General relativity
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Thoroughly Testing Einstein’s Special Relativity Theory, and More
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作者 Mario Rabinowitz 《Journal of Modern Physics》 2016年第1期87-105,共19页
Einstein’s Special Relativity (ESR) has enjoyed spectacular success as a mathematical construct and in terms of the experiments to which it has been subjected. Possible vulnerabilities of ESR will be explored that br... Einstein’s Special Relativity (ESR) has enjoyed spectacular success as a mathematical construct and in terms of the experiments to which it has been subjected. Possible vulnerabilities of ESR will be explored that break the symmetry of reciprocal observations of length, time, and mass. It is shown how Newton could also have derived length contraction . Einstein’s General Relativity (EGR) will also be discussed occasionally such as a changed perspective on gravitational waves due to a small change in ESR. Some additional questions addressed are: Did Einstein totally eliminate the Ether? Is the physical interpretation of ESR completely correct? Why should there be a maximum speed limit, and should it always be the same? The mass-energy equation is revisited to show that in 1717 Newton could have derived the modern , and not known that it violates the foundation of his mechanics. Tributes are paid to Einstein and others. 展开更多
关键词 Vulnerabilities of Special relativity Challenge of Reciprocal Observations of Length and Time EINSTEIN NEWTON Galilean Transformation Thought Experiments General relativity Gravitational Waves
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Mechanism of Quantum Consciousness that Synchronizes Quantum Mechanics with Relativity—Perspective of a New Model of Consciousness
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作者 Siva Prasad Kodukula 《Journal of Modern Physics》 2021年第12期1633-1655,共23页
Synchronization of quantum mechanics with relativity has been considered differently from the present quantum gravity models. It is originated from the roots of philosophy of physics and the basic concepts of relativi... Synchronization of quantum mechanics with relativity has been considered differently from the present quantum gravity models. It is originated from the roots of philosophy of physics and the basic concepts of relativity & quantum mechanics. It emphasizes the fact that two conscious observers are necessary to experience one conscious moment. Various concepts of consciousness have been discussed and emphasized the necessity for the introduction of a new model of quantum consciousness. A quantum coordinate system has been introduced to explain the present understanding of the phenomena “observation” and “reality”. It has been elaborated that the observation defined by physics is confined to Lorentz space time coordinate system, Minkowski coordinate system and general relativity. But phenomena of observation cannot be completed without considering one more hidden transformation explaining quantum coordinate system which transforms the quantum states into relativistic coordinate system as an interaction between two conscious observers explained by an interactive mechanism of quantum states. A flow chart has been illustrated by a mechanism giving rise to conscious moment and proposed a new model of consciousness. It emphasizes on the fact that “reality” is different from “observation” defined by physics. It affects the relativistic factor of special relativity and suggests a modification for it. If this modified relativistic factor is proved experimentally, the results establish consciousness’s mechanism and a remarkable breakthrough in physics of consciousness studies. 展开更多
关键词 Quantum Mechanics relativity Double relativity Effect Film Theory of Universe CONSCIOUSNESS
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Superrelativity
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作者 Peter Donald Rodgers 《Open Journal of Fluid Dynamics》 2016年第2期130-143,共14页
Did any physics experts expect SUPERRELATIVITY paper, a physics revolution producing the EINSTEIN-RODGERS RELATIVITY EQUATION, producing the HAWKING-RODGERS BLACK HOLE RADIUS, and producing the STEFAN-BOLTZMANN-SCHWAR... Did any physics experts expect SUPERRELATIVITY paper, a physics revolution producing the EINSTEIN-RODGERS RELATIVITY EQUATION, producing the HAWKING-RODGERS BLACK HOLE RADIUS, and producing the STEFAN-BOLTZMANN-SCHWARZSCHILD-HAWKING-RODGERS BLACK HOLE RADIATION POWER LAW, as the author gave a solution to The Clay Mathematics Institute’s very difficult problem about the Navier-Stokes Equations? The Clay Mathematics Institute in May 2000 offered that great $million prize to the first person providing a solution for a specific statement of the problem: “Prove or give a counter-example of the following statement: In three space dimensions and time, given an initial velocity field, there exists a vector velocity and a scalar pressure field, which are both smooth and globally defined, that solve the Navier-Stokes Equations.” Did I, the creator of this paper, expect SUPERRELATIVITY to become a sophisticated conversion of my unified field theory ideas and mathematics into a precious fluid dynamics paper to help mathematicians, engineers and astro-physicists? [1]. Yes, but I did not expect such superb equations that can be used in medicine or in outer space! In this paper, complicated equations for multi-massed systems become simpler equations for fluid dynamic systems. That simplicity is what is great about the Navier-Stokes Equations. Can I delve deeply into adding novel formulae into the famous Schwarzschild’s equation? Surprisingly, yes I do! Questioning the concept of reversibility of events with time, I suggest possible 3-dimensional and 4-dimensional co-ordinate systems that seem better than what Albert Einstein used, and I suggest possible modifications to Maxwell’s Equations. In SUPERRELATIVITY, I propose that an error exists in Albert Einstein’s Special Relativity equations, and that error is significant because it leads to turbulence in the universe’s fluids including those in our human bodies. Further, in SUPERRELATIVITY, after I create Schwarzschild-based equations that enable easy derivation of the Navier-Stokes Equations, I suddenly create very interesting exponential energy equations that simplify physics equations, give a mathematical reason for turbulence in fluids, give a mathematical reason for irreversibility of events with time, and enable easy derivation of the Navier-Stokes Equations. Importantly, my new exponential Navier-Stokes Equations are actually wave equations as should be used in Fluid Dynamics. Thrilled by my success, I challenge famous equations by Albert Einstein and Stephen Hawking [2] [3]. 展开更多
关键词 Superrelativity relativity Navier-Stokes Equation PHYSICS Albert Einstein Stephen Hawking Black Hole Clay Mathematics Institute
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Rethinking the Formal Methodology (II): Cognitive Content of Relativity (On the Centenary of General Relativity)
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作者 George Kirakosyan 《International Journal of Astronomy and Astrophysics》 2016年第1期23-55,共33页
An attempt to epistemological completion of formal-math theories of relativity is presented. Causal interpretations of SR and GR are suggested. The problem to physical gist of gravity is explained as a contradiction o... An attempt to epistemological completion of formal-math theories of relativity is presented. Causal interpretations of SR and GR are suggested. The problem to physical gist of gravity is explained as a contradiction of cognition vs. intuition. Gravity phenomena are represented as unexplored peculiarity of basic particles. The gravity constant is deduced from the known parameters of the electron. 展开更多
关键词 EINSTEIN Special relativity General relativity Gravity Constant
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Hamiltonian Formalism of de-Sitter Invariant Special Relativity 被引量:7
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作者 YAN Mu-Lin XIAO Neng-Chao HUANG Wei Interdisciplinary Center for Theoretical Study,University of Science and Technology of China,Hefei 230026,ChinaLI Si Department of Mathematics,University of Science and Technology of China,Hefei 230026,China 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第7期27-36,共10页
The Lagrangian of Einstein's special relativity with universal parameter c(SR_c)is invariant under Poincarétransformation,which preserves Lorentz metric η_μν.The SR_c has been extended to be one which is i... The Lagrangian of Einstein's special relativity with universal parameter c(SR_c)is invariant under Poincarétransformation,which preserves Lorentz metric η_μν.The SR_c has been extended to be one which is invariant underde Sitter transformation that preserves so-called Beltrami metric B_(μv).There are two universal parameters,c and R,inthis Special Relativity(denoted as SR_(cR)).The Lagrangian-Hamiltonian formulism of SR_(cR) is formulated in this paper.The canonic energy,canonic momenta,and 10 Noether charges corresponding to the space-time's,de Sitter symmetryare derived.The canonical quantization of the mechanics for SR_(CR)-free particle is performed.The physics related to itis discussed. 展开更多
关键词 de-Sitter invariance special relativity canonic energy and canonic momenta Beltrami metric
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Three Kinds of Special Relativity via Inverse Wick Rotation 被引量:4
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作者 郭汉英 黄超光 +1 位作者 徐湛 周彬 《Chinese Physics Letters》 SCIE CAS CSCD 2005年第10期2477-2480,共4页
Since the special relativity can be viewed as the physics in an inverse Wick rotation of four-dimensional (4D) Euclid space, which is at almost equal footing with the 4D Riemann/Lobachevski space, there should be im... Since the special relativity can be viewed as the physics in an inverse Wick rotation of four-dimensional (4D) Euclid space, which is at almost equal footing with the 4D Riemann/Lobachevski space, there should be important physics in the inverse Wick rotation of 4D Riemann/Lobachevski space. Thus, there are three kinds of special relativity in de Sitter(dS)/Minkowski/anti-de Sitter(AdS) space at almost equal footing, respectively. There is an instanton tunnelling scenario in the Riemann-de Sitter case that may explain why A be positive and link with the multiverse. 展开更多
关键词 INVARIANT SPECIAL relativity SITTER SPACETIME SUPERGRAVITY CONSTANT GRAVITY
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Dirac Oscillator Under the New Generalized Uncertainty Principle From the Concept Doubly Special Relativity 被引量:2
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作者 S.Sargolzaeipor H.Hassanabadi W.S.Chung 《Communications in Theoretical Physics》 SCIE CAS CSCD 2019年第11期1301-1303,共3页
We discuss one-dimensional Dirac oscillator, by using the concept doubly special relativity. We calculate the energy spectrum by using the concept doubly special relativity. Then, we derive another representation that... We discuss one-dimensional Dirac oscillator, by using the concept doubly special relativity. We calculate the energy spectrum by using the concept doubly special relativity. Then, we derive another representation that the coordinate operator remains unchanged at the high energy while the momentum operator is deformed at the high energy so that it may be bounded from the above. Actually, we study the Dirac oscillator by using of the generalized uncertainty principle version and the concept doubly special relativity. 展开更多
关键词 DIRAC EQUATION generalized uncertainty PRINCIPLE DOUBLY SPECIAL relativity
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Relativity stability of quantum gas in a weak magnetic field 被引量:2
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作者 门福殿 刘慧 +1 位作者 范召兰 朱后禹 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第9期3719-3723,共5页
Based on the analytical expression of relativistic free energy for a weakly interacting Fermi gas in a weak magnetic field, by using the method of quantum statistics, the stability conditions of the system at both hig... Based on the analytical expression of relativistic free energy for a weakly interacting Fermi gas in a weak magnetic field, by using the method of quantum statistics, the stability conditions of the system at both high and low temperatures are given, and the effects of magnetic field and interparticle interactions on the stability of the system are analysed. It is shown that at high temperatures, the stability conditions of the system are completely the same, no matter whether it is the ultrarelativistic case or nonrelativistic case. At extremely low temperatures, the mechanical stability conditions of the system show a similar rule through a comparison between the ultrarelativistic case and nonrelativistic case. At the same time, thermal stability of a relativistic Bose gas in a weak magnetic field is discussed, and the influence of the effect of relativity on the thermal stability of the system is investigated. 展开更多
关键词 quantum gas effect of relativity STABILITY
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The hyperbolic Extension of Sigalotti-Hendi-Sharifzadeh’s Golden Triangle of Special Theory of Relativity and the Nature of Dark Energy 被引量:9
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作者 M. S. El Naschie 《Journal of Modern Physics》 2013年第3期354-356,共3页
Previous work by Sigalotti in 2006 and recently by Hendi and Sharifzadeh in 2012 showed that all the fundamental equations of special relativity may be derived from a golden mean proportioned classical-Euclidean trian... Previous work by Sigalotti in 2006 and recently by Hendi and Sharifzadeh in 2012 showed that all the fundamental equations of special relativity may be derived from a golden mean proportioned classical-Euclidean triangle and confirmed Einstein’s famous equation E=mc2. In the present work it is shown that exchanging the Euclidean triangle with a hyperbolic one an extended quantum relativity energy equation, namely , is obtained. The relevance of this result in understanding the true nature of the “missing” so-called dark energy of the cosmos is discussed in the light of the fact that the ratio of to E=mc2 is which agrees almost completely with the latest supernova and WMAP cosmological measurements. To put it succinctly what is really missing is a quantum mechanical factor equal 1/22 in Einstein’s purely relativistic equation. This factor on the other hand is derivable from the intrinsic hyperbolic Cantor set nature of quantum entanglement. 展开更多
关键词 DARK ENERGY QUANTUM relativity DARK Dimensions HYPERBOLIC Geometry WMAP Measurement SUPERNOVA Analysis Ordinary ENERGY of QUANTUM Particles DARK ENERGY of QUANTUM Wave
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Remarks on the Total Angular Momentum in General Relativity 被引量:2
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作者 ZHANGXiao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第5期521-524,共4页
We verify that the total angular momentum 3-vector defined by the author [X. Zhang, Commun. Math.Phys. 206 (1999) 137] is equal to (0, 0, ma) forany time slice in both the Kerr and the Kerr-Newman spacetimes.
关键词 total angular momentum general relativity
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Classification of Relativity 被引量:4
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作者 Vu B. Ho 《Journal of Modern Physics》 2020年第4期535-564,共30页
In this work, we discuss the possibility to classify relativity in accordance with the classification of second order partial differential equations that have been applied into the formulation of physical laws in phys... In this work, we discuss the possibility to classify relativity in accordance with the classification of second order partial differential equations that have been applied into the formulation of physical laws in physics. In mathematics, since second order partial differential equations can be classified into hyperbolic, elliptic or parabolic type, therefore we show that it is also possible to classify relativity accordingly into hyperbolic, elliptic or parabolic type by establishing coordinate transformations that preserve the forms of these second order partial differential equations. The coordinate transformation that preserves the form of the hyperbolic equation is the Lorentz transformation and the associated space is the hyperbolic, or pseudo-Euclidean, relativistic spacetime. Typical equations in physics that comply with hyperbolic relativity are Maxwell and Dirac equations. The coordinate transformation that preserves the form of the elliptic equation is the modified Lorentz transformation that we have formulated in our work on Euclidean relativity and the associated space is the elliptic, or Euclidean, relativistic spacetime. As we will show in this work, equations that comply with elliptic relativity are the equations that describe the subfields of Maxwell and Dirac field. And the coordinate transformation that preserves the form of the parabolic equation is the Euclidean transformation consisting of the translation and rotation in the spatial space and the associated space is the parabolic relativistic spacetime, which is a Euclidean space with a universal time. Typical equations in physics that comply with parabolic relativity are the diffusion equation, the Schr&ouml;dinger equation and in particular the diffusion equations that are derived from the four-current defined in terms of the differentiable structures of the spacetime manifold, and the Ricci flow. 展开更多
关键词 Special relativity ELLIPTIC EQUATION HYPERBOLIC EQUATION PARABOLIC EQUATION ELLIPTIC relativity HYPERBOLIC relativity PARABOLIC relativity Classification of relativity Maxwell and DIRAC Field Maxwell and DIRAC Subfield
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One Electron Atom in Special Relativity with de Sitter Space-Time Symmetry(Ⅱ): ——Higher Order Contributions 被引量:1
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作者 闫沐霖 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第8期189-195,共7页
This is a follow of previous work entitled "One Electron Atom in Special Relativity with de Sitter SpaceTime Symmetry" [Commun. Theor. Phys. 57(2012) 930]. In this paper, we consider the higher order calcula... This is a follow of previous work entitled "One Electron Atom in Special Relativity with de Sitter SpaceTime Symmetry" [Commun. Theor. Phys. 57(2012) 930]. In this paper, we consider the higher order calculations and contributions in the previous framework to solve one electron atoms in de Sitter invariant relativistic quantum mechanics. The next-to-leading-order calculations in 1/R2-expansions show that the fine-structure constant α is variant with cosmologic time going by in the de Sitter invariant special relativistic quantum mechanics with standard FRW cosmologic model. 展开更多
关键词 hydrogen ATOM special relativity with de SITTER space-time symmetry time variation of physical CONSTANTS Friedmann–Robertson–Walker(FRW) UNIVERSE
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Hidden Symmetries for Thermodynamics and Emergence of Relativity 被引量:1
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作者 赵柳 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期641-646,共6页
Erik Verlinde recently proposed an idea about the thermodynamic origin of gravity.Though this is abeautiful idea, which may resolve many long standing problems in the theories of gravity, it also raises many otherprob... Erik Verlinde recently proposed an idea about the thermodynamic origin of gravity.Though this is abeautiful idea, which may resolve many long standing problems in the theories of gravity, it also raises many otherproblems.In this article I will comment on some of the problems of Verlinde’s proposal with special emphasis on thethermodynamical origin of the principle of relativity.It is found that there is a large group of hidden symmetries ofthermodynamics, which contains the Poincare group of the spacetime for which space is emergent.This explains thethermodynamic origin of the principle of relativity. 展开更多
关键词 emergent gravity THERMODYNAMICS GEOMETRY principle of relativity
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