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Trace Formulae of Characteristic Polynomial and Cayley-HamUton's Theorem, and Applications to Chiral Perturbation Theory and General Relativity
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作者 ZHANG Hong-Hao YAN Wen-Bin LI Xue-Song 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第4期801-808,共8页
By using combinatorics, we give a new proof for the recurrence relations of the characteristic polynomial coefficients, and we further obtain an explicit expression for the generic term of the coefficient sequence, wh... By using combinatorics, we give a new proof for the recurrence relations of the characteristic polynomial coefficients, and we further obtain an explicit expression for the generic term of the coefficient sequence, which yields the trace formulae of the Cayley-Hamilton's theorem with all coefficients explicitly given. This implies a byproduct, a complete expression for the determinant of any finite-dimensional matrix in terms of the traces of its successive powers. And we discuss some of their applications to ehiral perturbation theory and general relativity. 展开更多
关键词 characteristic polynomial coefficients Cayley-Hamilton's theorem chiral perturbation theory general relativity
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Einstein’s General Relativity and Pure Gravity in a Cosserat and De Sitter-Witten Spacetime Setting as the Explanation of Dark Energy and Cosmic Accelerated Expansion
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作者 Mohamed S. El Naschie 《International Journal of Astronomy and Astrophysics》 2014年第2期332-339,共8页
Ordinary energy and dark energy density are determined using a Cosserat-Cartan and killing-Yano reinterpretation of Einstein’s special and general relativity. Thus starting from a maximally symmetric space with 528 k... Ordinary energy and dark energy density are determined using a Cosserat-Cartan and killing-Yano reinterpretation of Einstein’s special and general relativity. Thus starting from a maximally symmetric space with 528 killing vector fields corresponding to Witten’s five Branes model in eleven dimensional M-theory we reason that 504 of the 528 are essentially the components of the relevant killing-Yano tensor. In turn this tensor is related to hidden symmetries and torsional coupled stresses of the Cosserat micro-polar space as well as the Einstein-Cartan connection. Proceeding in this way the dark energy density is found to be that of Einstein’s maximal energy mc2 where m is the mass and c is the speed of light multiplied with a Lorentz factor equal to the ratio of the 504 killing-Yano tensor and the 528 states maximally symmetric space. Thus we have E (dark) = mc2 (504/528) = mc2 (21/22) which is about 95.5% of the total maximal energy density in astounding agreement with COBE, WMAP and Planck cosmological measurements as well as the type 1a supernova analysis. Finally theory and results are validated via a related theory based on the degrees of freedom of pure gravity, the theory of nonlocal elasticity as well as ‘t Hooft-Veltman renormalization method. 展开更多
关键词 general relativity COssERAT Micro-Polar space Dark Energy Teleparellelism Witten’s M-theory De sitter sPACETIME Killing-Yano Tensor einstein-Cartan relativity PURE GRAVITY Kaluza-Klein theory Nonlocal Elasticity 't Hooft-Veltman Renormalization
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Class of Charged Fluid Balls in General Relativity 被引量:2
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作者 A. Sah Prakash Chandra 《International Journal of Astronomy and Astrophysics》 2016年第4期494-511,共18页
In the present study, we have obtained a new analytical solution of combined Einstein-Maxwell field equations describing the interior field of a ball having static spherically symmetric isotropic charged flu... In the present study, we have obtained a new analytical solution of combined Einstein-Maxwell field equations describing the interior field of a ball having static spherically symmetric isotropic charged fluid within it. The charge and electric field intensity are zero at the center and monotonically increasing towards the boundary of the fluid ball. Besides these, adiabatic index is also increasing towards the boundary and becomes infinite on it. All other physical quantities such as pressure, density, adiabatic speed of sound, charge density, adiabatic index are monotonically decreasing towards the surface. Causality condition is obeyed at the center of ball. In the limiting case of vanishingly small charge, the solution degenerates into Schwarzchild uniform density solution for electrically neutral fluid. The solution joins smoothly to the Reissner-Nordstrom solution over the boundary. We have constructed a neutron star model by assuming the surface density . The mass of the neutron star comes  with radius 14.574 km. 展开更多
关键词 Exact solution einsteins Field Equations Charged Fluid Ball Compact star general relativity
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General Relativity without Curved Space-Time (&#8370;R)
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作者 Abed El Karim S. Abou Layla 《Journal of High Energy Physics, Gravitation and Cosmology》 2019年第1期156-166,共11页
The theory of general relativity is related to the concept of curvature of space- time induced by the presence of the massive objects. We will see through this paper that the general relativity can be linked with line... The theory of general relativity is related to the concept of curvature of space- time induced by the presence of the massive objects. We will see through this paper that the general relativity can be linked with linear Algebra and Vector Analysis without the need for concept of space-time. This is important for the unification of general relativity with quantum mechanics, gravity with electromagnetic, and a better understanding of the universe, gravity, black holes. The most important is the separation between the space-time and the big bang theory, which prove the existence of space-time before that, which leads to the existence of the creator of the universe. 展开更多
关键词 Gravity Electromagnetism BIG Bang sPACE-TIME general relativity LORENTZ Force Density The einsteins TENsOR
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Why Krogdahl’s Flat Space-Time Cosmology Is Superior to General Relativity
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2017年第13期2087-2095,共9页
This paper briefly discusses existing problems with the theory of general relativity despite remarkable accuracy in most of its applications. The primary focus is on existing problems in the field of cosmology, partic... This paper briefly discusses existing problems with the theory of general relativity despite remarkable accuracy in most of its applications. The primary focus is on existing problems in the field of cosmology, particularly those pertaining to expectations of global cosmic space-time curvature in the absence of observational proof. The discussion centers on Krogdahl’s recent Lorentz-invariant flat space-time cosmology and its superiority to general relativity with respect to accounting for global cosmic space-time flatness and dark energy observations. The “cosmological constant problem” is briefly addressed as a problem for general relativity with respect to particle physics and quantum field theory. Finally, two very specific validation predictions in favor of Krogdahl’s flat space-time cosmology are made with respect to ongoing studies, including the dark energy survey (DES). 展开更多
关键词 COsMOLOGICAL theory general relativity FLATNEss PROBLEM COsMIC Infla-tion Dark Energy survey COsMOLOGICAL Constant PROBLEM Krogdahl’s relativity
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Why the Road to Unification Likely Goes through Krogdahl’s Relativity
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2017年第13期2096-2103,共8页
Deriving an acceptable quantum field theory of gravitation from general relativity has eluded some of the best scientific thinkers. It is gradually becoming more apparent that general relativity’s classical assumptio... Deriving an acceptable quantum field theory of gravitation from general relativity has eluded some of the best scientific thinkers. It is gradually becoming more apparent that general relativity’s classical assumptions are simply incompatible with quantum mechanics. For instance, simultaneous certainty of the location and momentum of any moving body, regardless of size, is a fundamental feature of general relativity. And yet, special relativity and quantum mechanics (thru Heisenberg’s uncertainty) reject the very notion of simultaneity. Since special relativity is already fully integrated into quantum field theory concerning the other forces of nature, were it possible to remove the confounding smoothly curved space-time fabric of general relativity and replace it in the form of a new and improved Lorentz-invariant (flat space-time) gravitational theory, final unification might well be achievable. This brief review paper further informs the reader as to why Krogdahl’s recent Lorentz-invariant relativity model of gravitation improves on general relativity, thus providing a deeper understanding of black holes, the cosmological flatness problem and dark energy. Most importantly, since the smoothly curved space-time of general relativity may well have been the road block to unification, Krogdahl’s flat space-time model is predicted to lead to an acceptable quantum theory of gravitation (i.e., “quantum gravity”) and unification (i.e., a so-called “theory of everything”). 展开更多
关键词 COsMOLOGICAL theory general relativity FLATNEss PROBLEM Black Holes Dark Energy COsMOLOGICAL Constant PROBLEM Krogdahl’s relativity
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Entanglement of E8E8 Exceptional Lie Symmetry Group Dark Energy, Einstein’s Maximal Total Energy and the Hartle-Hawking No Boundary Proposal as the Explanation for Dark Energy 被引量:7
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作者 Mohamed S. El Naschie 《World Journal of Condensed Matter Physics》 2014年第2期74-77,共4页
The present note is concerned with two connected and highly important fundamental questions of physics and cosmology, namely if E8E8 Lie symmetry group describes the universe and where cosmic dark energy comes from. F... The present note is concerned with two connected and highly important fundamental questions of physics and cosmology, namely if E8E8 Lie symmetry group describes the universe and where cosmic dark energy comes from. Furthermore, we reason following Wheeler, Hartle and Hawking that since the boundary of a boundary is an empty set which models the quantum wave of the cosmos, then it follows that dark energy is a fundamental physical phenomenon associated with the boundary of the holographic boundary. This leads directly to a clopen universe which is its own Penrose tiling-like multiverse with energy density in full agreement with COBE, WMAP and Type 1a supernova cosmic measurements. 展开更多
关键词 E8 Exceptional Lie symmetry GROUP Dark Energy einsteins relativity E-INFINITY theory Wheeler BOUNDARY of a BOUNDARY Hartle-Hawking NO BOUNDARY PROPOsAL Penrose Tiling Multiverse
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A Spherical Relativistic Anisotropic Compact Star Model 被引量:1
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作者 Prakash Chandra Fulara Archana Sah 《International Journal of Astronomy and Astrophysics》 2018年第1期46-67,共22页
We provide solutions to Einsteins field equations for a model of a spherically symmetric anisotropic fluid distribution, relevant to the description of compact stars. The central matter-energy density, radial and tang... We provide solutions to Einsteins field equations for a model of a spherically symmetric anisotropic fluid distribution, relevant to the description of compact stars. The central matter-energy density, radial and tangential pressures, red shift and speed of sound are positive definite and are decreasing monotonically with increasing radial distance from the center of matter distribution of astrophysical object. The causality condition is satisfied for complete fluid distribution. The central value of anisotropy is zero and is increasing monotonically with increasing radial distance from the center of the distribution. The adiabatic index is increasing with increasing radius of spherical fluid distribution. The stability conditions in relativistic compact star are also discussed in our investigation. The solution is representing the realistic objects such as SAXJ1808.4-3658, HerX-1, 4U1538-52, LMC X-4, CenX-3, VelaX-1, PSRJ1614-2230 and PSRJ0348+0432 with suitable conditions. 展开更多
关键词 ANIsOTROPIC Fluid Distribution Non sINGULAR solutions einsteins Field Equations super DENsE star general relativity
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Airy, Beltrami, Maxwell, Einstein and Lanczos Potentials Revisited 被引量:1
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作者 J.-F. Pommaret 《Journal of Modern Physics》 2016年第7期699-728,共30页
The purpose of this paper is to revisit the well known potentials, also called stress functions, needed in order to study the parametrizations of the stress equations, respectively provided by G.B. Airy (1863) for 2-d... The purpose of this paper is to revisit the well known potentials, also called stress functions, needed in order to study the parametrizations of the stress equations, respectively provided by G.B. Airy (1863) for 2-dimensional elasticity, then by E. Beltrami (1892), J.C. Maxwell (1870) for 3-dimensional elasticity, finally by A. Einstein (1915) for 4-dimensional elasticity, both with a variational procedure introduced by C. Lanczos (1949, 1962) in order to relate potentials to Lagrange multipliers. Using the methods of Algebraic Analysis, namely mixing differential geometry with homological algebra and combining the double duality test involved with the Spencer cohomology, we shall be able to extend these results to an arbitrary situation with an arbitrary dimension n. We shall also explain why double duality is perfectly adapted to variational calculus with differential constraints as a way to eliminate the corresponding Lagrange multipliers. For example, the canonical parametrization of the stress equations is just described by the formal adjoint of the  components of the linearized Riemann tensor considered as a linear second order differential operator but the minimum number of potentials needed is equal to for any minimal parametrization, the Einstein parametrization being “in between” with potentials. We provide all the above results without even using indices for writing down explicit formulas in the way it is done in any textbook today, but it could be strictly impossible to obtain them without using the above methods. We also revisit the possibility (Maxwell equations of electromagnetism) or the impossibility (Einstein equations of gravitation) to obtain canonical or minimal parametrizations for various equations of physics. It is nevertheless important to notice that, when n and the algorithms presented are known, most of the calculations can be achieved by using computers for the corresponding symbolic computations. Finally, though the paper is mathematically oriented as it aims providing new insights towards the mathematical foundations of general relativity, it is written in a rather self-contained way. 展开更多
关键词 stress Equations stress Functions Elasticity theory Lagrange Multipliers Formal Adjoint Control theory general relativity einstein Equations Lanczos Potentials Algebraic Analysis Riemann Tensor Weyl Tensor
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The Singularities of Gravitational Fields of Static Thin Loop and Double Spheres Reveal the Impossibility of Singularity Black Holes 被引量:2
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作者 Xiaochun Mei 《Journal of Modern Physics》 2013年第7期974-982,共9页
In the classical Newtonian mechanics, the gravity fields of static thin loop and double spheres are two simple but foundational problems. However, in the Einstein’s theory of gravity, they are not simple. In fact, we... In the classical Newtonian mechanics, the gravity fields of static thin loop and double spheres are two simple but foundational problems. However, in the Einstein’s theory of gravity, they are not simple. In fact, we do not know their solutions up to now. Based on the coordinate transformations of the Kerr and the Kerr-Newman solutions of the Einstein’s equation of gravity field with axial symmetry, the gravity fields of static thin loop and double spheres are obtained. The results indicate that, no matter how much the mass and density are, there are singularities at the central point of thin loop and the contact point of double spheres. What is more, the singularities are completely exposed in vacuum. Space near the surfaces of thin loop and spheres are highly curved, although the gravity fields are very weak. These results are inconsistent with practical experience and completely impossible. By reasonable analogy, black holes with singularity in cosmology and astrophysics are something illusive. Caused by the mathematical description of curved space-time, they do not exist in real world actually. If there are black holes in the universe, they can only be the types of the Newtonian black holes without singularities, rather than the Einstein’s singularity black holes. In order to escape the puzzle of singularity thoroughly, the description of gravity should return to the traditional form of dynamics in flat space. The renormalization of gravity and the unified description of four basic interactions may be possible only based on the frame of flat space-time. Otherwise, theses problems can not be solved forever. Physicists should have a clear understanding about this problem. 展开更多
关键词 general relativity The einsteins Equation of Gravity FIELD Axially symmetrical solutions sINGULARITY Kerr METRIC Kerr-Newman METRIC GRAVITATIONAL FIELD of static Thin LOOP GRAVITATIONAL FIELD of Double sPHEREs Black Hole Quasar MECO
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A Potentially Unifying Constant of Nature (Brief Note)
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作者 Eugene Terry Tatum U. V. S. Seshavatharam S. Lakshminarayana 《Journal of Modern Physics》 2021年第6期739-743,共5页
This brief note describes a method by which numerous empirically-determined quantum constants of nature can be substituted into Einstein’s field equation (EFE) for general relativity. This method involves treating th... This brief note describes a method by which numerous empirically-determined quantum constants of nature can be substituted into Einstein’s field equation (EFE) for general relativity. This method involves treating the ratio <em>G/<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#1115;</span></span></span></span></em> as an empirical constant of nature in its own right. This ratio is repre- sented by a new symbol, <em>N</em><sub><em>T</em></sub>. It turns out that the value of <em>N</em><sub><em>T</em></sub> (which is 6.32891937 × 10<sup>23</sup> m<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&sdot;</span></span></span></span></span></span>kg<sup>-2</sup><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&sdot;</span></span></span></span></span></span>s<sup>-1</sup>) is within 5% of Avogadro’s number<em> N</em><sub><em>A</em></sub>, although the units are clearly different. Nevertheless, substitutions of <em>N</em><sub><em>T</em></sub> or <em>N</em><sub><em>A</em></sub> into the EFE, as shown, should yield an absolute value similar in magnitude to that calculated by the conventional EFE. The method described allows for quantum term EFE substitutions into Einstein’s gravitational constant <em>κ</em>. These terms include <em><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#1115;</span></span></span></span></em>, <em>α</em>, <em>m</em><sub><em>e</em></sub>, <em>m</em><sub><em>p</em></sub>, <em>R</em>, <em>k</em><sub><em>B</em></sub>, <em>F, e, M<sub>U</sub></em>, and <em>m</em><sub><em>U</em></sub>. More importantly, perhaps, one or more of the many new expressions given for <em>κ</em> may provide a more accurate result than <em>κ</em> incorporating <em>G</em>. If so, this may have important implications for additional forward progress towards unification. Whether any of these new expressions for Einstein’s field equation can move us closer to quantizing gravity remains to be determined. 展开更多
关键词 Unification general relativity Quantum theory einsteins Gravitational Constant Tatum’s Number Avogadro’s Number
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Computing Dark Energy and Ordinary Energy of the Cosmos as a Double Eigenvalue Problem
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作者 Mohamed S. El Naschie 《Journal of Modern Physics》 2015年第4期384-395,共12页
We compute the dark energy and ordinary energy density of the cosmos as a double Eigenvalue problem. In addition, we validate the result using two different theories. The first theory is based on Witten’s 11 dimensio... We compute the dark energy and ordinary energy density of the cosmos as a double Eigenvalue problem. In addition, we validate the result using two different theories. The first theory is based on Witten’s 11 dimensional spacetime and the second is based on ‘tHooft’s fractal renormalization spacetime. In all cases, the robust result is E(O) = mc2/22 for ordinary energy and E(D) = mc2(21/22) for dark energy. Adding E(O) to E(D) we obtain Einstein’s famous equation which confirms special relativity, although it adds a quantum twist to its interpretation. This new interpretation is vital because it brings relativity theory in line with modern cosmological measurements and observations. In particular, we replace calculus by Weyl scaling in all computation which is essentially transfinite discrete. 展开更多
关键词 DOUBLE Eigenvalues WEYL scaling Magueijo-smolin ENERGY Formula Dark ENERGY einsteins relativity E-INFINITY theory
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Two Physical Constraints upon the Motions of Celestial Bodies
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作者 Xiaobai Ai 《Journal of Modern Physics》 2019年第3期344-361,共18页
There exist two physical constraints upon the motions of celestial systems. Constraint 1 reveals during collapse or explosion motion of celestial bodies that there would be an unattainability upper limit for their com... There exist two physical constraints upon the motions of celestial systems. Constraint 1 reveals during collapse or explosion motion of celestial bodies that there would be an unattainability upper limit for their compact intensity (total mass M/scale size R), which arises from the Lorentz invariance of the time-like metric in local four-dimensional continuum in Einstein’s theory of special relativity. Constraint 2 points that the average mass density of nucleon would be an unsurpassed upper limit for bulk normal matter in nature, which arises from Heisenberg’s uncertainty principle. A very important effect is that the combination of these two physical constraints would prevent the formation of black holes. 展开更多
关键词 general theory of relativity GRAVITATION COLLAPsING sCHWARZsCHILD Metric sCHWARZsCHILD sINGULARITY Centre sINGULARITY Black Hole Compact Intensity Heisenberg’s Uncertainty Principle
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Why Gravitational Waves Cannot Exist
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作者 J.-F. Pommaret 《Journal of Modern Physics》 2017年第13期2122-2158,共37页
The purpose of this short but difficult paper is to revisit the mathematical foundations of both General Relativity (GR) and Gauge Theory (GT) in the light of a modern approach to nonlinear systems of ordinary or part... The purpose of this short but difficult paper is to revisit the mathematical foundations of both General Relativity (GR) and Gauge Theory (GT) in the light of a modern approach to nonlinear systems of ordinary or partial differential equations, using new methods from Differential Geometry (D.C. Spencer, 1970), Differential Algebra (J.F. Ritt, 1950 and E. Kolchin, 1973) and Algebraic Analysis (M. Kashiwara, 1970). The main idea is to identify the differential indeterminates of Ritt and Kolchin with the jet coordinates of Spencer, in order to study Differential Duality by using only linear differential operators with coefficients in a differential field K. In particular, the linearized second order Einstein operator and the formal adjoint of the Ricci operator are both parametrizing the 4 first order Cauchy stress equations but cannot themselves be parametrized. In the framework of Homological Algebra, this result is not coherent with the vanishing of a certain second extension module and leads to question the proper origin and existence of gravitational waves. As a byproduct, we also prove that gravitation and electromagnetism only depend on the second order jets (called elations by E. Cartan in 1922) of the system of conformal Killing equations because any 1-form with value in the bundle of elations can be decomposed uniquely into the direct sum (R, F) where R is a section of the Ricci bundle of symmetric covariant 2-tensors and the EM field F is a section of the vector bundle of skew-symmetric 2-tensors. No one of these purely mathematical results could have been obtained by any classical approach. Up to the knowledge of the author, it is also the first time that differential algebra in a modern setting is applied to study the specific algebraic feature of most equations to be found in mathematical physics, particularly in GR. 展开更多
关键词 general relativity Riemann TENsOR Weyl TENsOR Ricci TENsOR einstein Equations Elastic WAVEs Gravitational WAVEs LIE Groups LIE Pseudogroups Differential Galois theory sPENCER Operator Janet sEQUENCE sPENCER sEQUENCE Differential MODULEs Algebraic Analysis Homological Algebra Extension MODULEs split Exact sEQUENCE
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A Combined Heterotic String and Kähler Manifold Elucidation of Ordinary Energy,Dark Matter,Olbers’s Paradox and Pure Dark Energy Density of the Cosmos
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作者 Mohamed S.El Naschie 《Journal of Modern Physics》 2017年第7期1101-1118,共18页
We utilize the topological-geometrical structure imposed by the Heterotic superstring theory on spacetime in conjunction with the K3 K&auml;hler manifold to explain the mysterious nature of dark matter and its cou... We utilize the topological-geometrical structure imposed by the Heterotic superstring theory on spacetime in conjunction with the K3 K&auml;hler manifold to explain the mysterious nature of dark matter and its coupling to the pure dark energy density of the cosmos. The analogous situations in the case of a Kerr black hole as well as the redundant components of the Riemannian tensor are pointed out and the final result was found to be in complete agreement with all previous theoretical ones as well as all recent accurate measurements and cosmic observations. We conclude by commenting briefly on the Cantorian model of Zitterbewegung and the connection between Olbers’s paradox and dark energy. 展开更多
关键词 Heterotic strings K3 Kahler Manifold Dark Matter Pure Heterotic Dark Energy einsteins relativity Accelerated Cosmic Expansion Negative Gravity Fractal spacetime E-Infinity theory Kerr Black Holes Geometry Kaluza-Klein theory Dvoretzky’s Theorem Empty set Zero set Connes Noncommutative Geometry ‘tHooft Renormalon sTATE Vector Reduction Density Matrix ‘tHooft Fractal spacetime Transfinite Cellular Automata Interpretation of Quantum Mechanics ZITTERBEWEGUNG Olberss Dark sky Paradox
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狭义相对论矛盾方程探讨 被引量:5
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作者 胡清桂 《河南理工大学学报(自然科学版)》 CAS 2009年第1期127-131,共5页
研究洛伦兹变换关系式与狭义相对论的关系,采用2种不同的方法分别揭示在狭义相对论中存在的矛盾方程.第1种方法是将坐标系S原点O和坐标系S′原点O′对应的参数值分别代入洛伦兹变换关系式x′=γ(x-vt)和x=γ(x′+vt′)中,得到矛盾方程;... 研究洛伦兹变换关系式与狭义相对论的关系,采用2种不同的方法分别揭示在狭义相对论中存在的矛盾方程.第1种方法是将坐标系S原点O和坐标系S′原点O′对应的参数值分别代入洛伦兹变换关系式x′=γ(x-vt)和x=γ(x′+vt′)中,得到矛盾方程;第2种方法是采用狭义相对论的结论"动钟变慢"的推导过程进一步重新推导,得到矛盾方程,从而证明狭义相对论在逻辑上是值得商榷的. 展开更多
关键词 相对论 爱因斯坦 坐标系s ′坐标系s
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Deviation of light path in Born-Infeld type gravitational field 被引量:1
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作者 张可锋 黄增光 +1 位作者 方伟 陆惠卿 《Journal of Shanghai University(English Edition)》 CAS 2006年第6期497-499,共3页
The discovery of "twin quasi-stellar objects" arose interests among astronomers and astrophysicists to study gravitational leasing problem. Deviation of light from straight path is caused by the presence of massive ... The discovery of "twin quasi-stellar objects" arose interests among astronomers and astrophysicists to study gravitational leasing problem. Deviation of light from straight path is caused by the presence of massive objects, i.e., the presence of gravitational field according to the general theory of relativity. It is shown that the low energy effective field theory on D-branes is of the Born-Infeld type. In this work a Born-Infeld type gravitational field is pasttflated. An explicit representation of the angular deviation of light path is derived based on the space time metric in the Born-Infeld theory. 展开更多
关键词 Bom-Infeld theory einstein's general relativity theory deviation of light path.
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线性化爱因斯坦场方程
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作者 代洪霞 《重庆工商大学学报(自然科学版)》 2005年第2期202-204,共3页
爱因斯坦场方程的非线性性给广义相对论的求解带来许多困难,在弱场情况下,可用近似处理的方法,把高度非线性的场方程变为线性场方程,简化了方程的求解。
关键词 爱因斯坦场方程 线性化 广义相对论 非线性性 近似处理 求解
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A note on the novel 4D Einstein–Gauss–Bonnet gravity 被引量:1
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作者 Wen-Yuan Ai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2020年第9期89-95,共7页
Recently, a novel 4 D Einstein–Gauss–Bonnet gravity has been proposed by Glavan and Lin(2020 Phys. Rev. Lett. 124 081301) by rescaling the coupling α→α(D-4) and taking the limit D→ 4 at the level of equations of... Recently, a novel 4 D Einstein–Gauss–Bonnet gravity has been proposed by Glavan and Lin(2020 Phys. Rev. Lett. 124 081301) by rescaling the coupling α→α(D-4) and taking the limit D→ 4 at the level of equations of motion. This prescription, though was shown to bring non-trivial effects for some spacetimes with particular symmetries, remains mysterious and calls for scrutiny. Indeed, there is no continuous way to take the limit D→4 in the higher Ddimensional equations of motion because the tensor indices depend on the spacetime dimension and behave discretely. On the other hand, if one works with 4 D spacetime indices the contribution corresponding to the Gauss–Bonnet term vanishes identically in the equations of motion. A necessary condition(but may not be sufficient) for this procedure to work is that there is an embedding of the 4 D spacetime into the higher D-dimensional spacetime so that the equations in the latter can be properly interpreted after taking the limit. In this note, working with2 D Einstein gravity, we show several subtleties when applying the method used in(2020 Phys.Rev. Lett. 124 081301). 展开更多
关键词 einstein–Gauss–Bonnet gravity modified gravity theories general relativity
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爱因斯坦狭义相对论——一个老年初学者为学生们写的评述 被引量:1
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作者 江涛 《大学物理》 北大核心 2007年第11期13-19,共7页
以一个爱因斯坦狭义相对论的老年初学者的角度,对狭义相对论的主要内容作了评述,其中若干表述是基于作者自己的学习心得.
关键词 狭义相对论 时间 空间 速度 红移
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