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1.
A solution to the Einstein field equations that represents a rigidly rotating dust accompanied by a thin matter shell of the same type is found.  相似文献   

2.
For general relativistic spacetimes filled with irrotational dust a generalized form of Friedmann's equations for an effective expansion factor a D of inhomogeneous cosmologies is derived. Contrary to the standard Friedmann equations, which hold for homogeneous-isotropic cosmologies, the new equations include the backreaction effect of inhomogeneities on the average expansion of the model. A universal relation between backreaction and average scalar curvature is also given. For cosmologies whose averaged spatial scalar curvature is proportional to a D -2, the expansion law governing a generic domain can be found. However, as the general equations show, backreaction acts as to produce average curvature in the course of structure formation, even when starting with space sections that are spatially flat on average.  相似文献   

3.
发展非线性耦合环境下精确、非微扰的量子耗散方法仍然是一个巨大的挑战.本文针对线性和二次耦合热浴模型,介绍了两种刻画系统与环境耦合动力学的有效方法.一个是耗散子运动方程(DEOM)理论,最近已被扩展到处理非线性耦合环境.另一个是推广的福克-普朗克量子主方程(FP-QME)方法,将在这项工作中基于DEOM推导给出.本文对这两种方法进行了详细的比较,并重点介绍了所涉及的准粒子图像、物理含义以及实现方案.  相似文献   

4.
The master equation is quantized. This is an example of quantization of a gauge theory with nilpotent generators. No ghosts are needed for the generation of a gauge algebra. The point about nilpotent generators is that one can not write down a single functional integral for this theory. Instead, one has to write down a product of two coupled functional integrals and take a square root. In a special gauge where the gauge conditions are commuting, the functional integrals decouple and one recovers the known result.  相似文献   

5.
Invariant operator method for discrete or continuous spectrum eigenvalue and unitary transformation approach are employed to study the two-dimensional time-dependent Pauli equation in presence of the Aharonov-Bohm effect (AB) and external scalar potential. For the spin particles the problem with the magnetic field is that it introduces a singularity into wave equation at the origin. A physical motivation is to replace the zero radius flux tube by one of radius R, with the additional condition that the magnetic field be confined to the surface of the tube, and then taking the limit R → 0 at the end of the computations. We point that the invariant operator must contain the step function θ(r - R). Consequently, the problem becomes more complicated. In order to avoid this dimculty, we replace the radius R by ρ(t)R, where ρ(t) is a positive time-dependent function. Then at the end of calculations we take the limit R →0. The qualitative properties for the invariant operator spectrum are described separately for the different values of the parameter C appearing in the nonlinear auxiliary equation satisfied by p(t), i.e., C 〉 0, C = 0, and C 〈0. Following the C's values the spectrum of quantum states is discrete (C 〉 0) or continuous (C ≤ 0).  相似文献   

6.
爱因斯坦用了10年时间分5步从狭义相对论提升到广义相对论及引力场方程,本文对此过程进行了逻辑梳理并辅助解释推导过程。  相似文献   

7.
WU Ning 《理论物理通讯》2008,49(1):129-132
Based on the coupfing between the spin of a particle and gravitoelectromagnetic field, the equation of motion of a spinning test particle in gravitational field is deduced. From this equation of motion, it is found that the motion of a spinning particle deviates from the geodesic trajectory, and this deviation originates from the coupling between the spin of the particle and gravitoelectromagnetic field, which is also the origin of Lense-Thirring effects. In post-Newtonian approximations, this equation gives the same results as those of Mathisson-Papapetrou equation. Effect of the deviation of geodesic trajectory is detectable.  相似文献   

8.
A novel dynamics equation of elastic rotation shaft possessing twin side based on the theory of relativityis built in this paper. The equation is established in different coordinate systems, which can provide the foundationtheoretically and methods for the similarity engineering and the similarity calibration of instruments used for measuring,observing, and controlling.  相似文献   

9.
A novel dynamics equation of elastic rotation shaft possessing twin side based on the theory of relativity is built in this paper. The eql~tion is established in different coordinate systems, which can provide the foundation theoretically and methods for the similarity engineering and the similarity calibration of instruments used for measuring,observing, and controlling.  相似文献   

10.
An infinite class of magnetized line-source (wire) metrics are here derived within the 5D GR (Kaluza-Klein) formalism. These metrics are cylindrically-symmetric (thus representing line-sources), and off-diagonal (thereby representing magnetized wire sources). The off-diagonality of these metrics is significant as all prior cylindrically-symmetric 5D GR metrics have been diagonal. In Kaluza-Klein theory, the vector potentials of EM are incorporated into the extended off-diagonal components of the metric. Thus, examination of such off-diagonal line source (magnetized wire) metrics is a hitherto untapped potential for 5D GR investigation.  相似文献   

11.
The equation of motion and molecular dynamics for simulating lattice field theory using the Hybrid Monte Carlo (HMC) algorithm are described. Some techniques for improving the HMC efficiency are discussed.  相似文献   

12.
No Heading In this paper we treat the so called clock paradox in an analytical way by assuming that a constant and uniform force F of finite magnitude acts continuously on the moving clock along the direction of its motion assumed to be rectilinear (in space). No inertial motion steps are considered. The rest clock is denoted as (1), the to and fro moving clock is (2), the inertial frame in which (1) is at rest in its origin and (2) is seen moving is I and, finally, the accelerated frame in which (2) is at rest in its origin and (1) moves forward and backward is A. We deal with the following questions: (1) What is the effect of the finite force acting on (2) on the proper time interval (2) measured by the two clocks when they reunite? Does a differential aging between the two clocks occur, as it happens when inertial motion and infinite values of the accelerating force is considered? The special theory of relativity is used in order to describe the hyperbolic (in spacetime) motion of (2) in the frame I. (II) Is this effect an absolute one, i.e., does the accelerated observer A comoving with (2) obtain the same results as that obtained by the observer in I, both qualitatively and quantitatively, as it is expected? We use the general theory of relativity in order to answer this question. It turns out that I = A for both the clocks, (2) does depend on g = F/m, and = (2)/(1) = (1 – 2atanhj)/ < 1. In it ; = V/c and V is the velocity acquired by (2) when the force is inverted.  相似文献   

13.
WU Ning 《理论物理通讯》2007,48(3):469-472
In general relativity, the equation of motion of the spin is given by the equation of parallel transport, which is a result of the space-time geometry. Any result of the space-time geometry cannog be directly applied to gauge theory of gravity. In gauge theory of gravity, based on the viewpoint of the coupling between the spin and gravitational field, an equation of motlon of the spin is deduced. In the post Newtonian approximation, it is proved that this equation gives the same result as that of the equation of parallel transport. So, in the post Newtonian approximation, gauge theory of gravity gives out the same prediction on the precession of orbiting gyroscope as that of general relativity.  相似文献   

14.
Herein we present a whole new approach that leads to the end results of the general theory of relativity via just the law of conservation of energy (broadened to embody the mass and energy equivalence of the special theory of relativity) and quantum mechanics. We start with the following postulate. Postulate: The rest mass of an object bound to a celestial body amounts less than its rest mass measured in empty space, and this, as much as its binding energy vis-á-vis the gravitational field of concern.  相似文献   

15.
WU Ning   《理论物理通讯》2007,48(9):469-472
In general relativity, the equation of motion of the spin is given by the equation of parallel transport, which is a result of the space-time geometry. Any result of the space-time geometry cannot be directly applied to gauge theory of gravity. In gauge theory of gravity, based on the viewpoint of the coupling between the spin and gravitational field,an equation of motion of the spin is deduced. In the post Newtonian approximation, it is proved that this equation gives the same result as that of the equation of parallel transport. So, in the post Newtonian approximation, gauge theory of gravity gives out the same prediction on the precession of orbiting gyroscope as that of general relativity.  相似文献   

16.
17.
It is shown that homogeneous plane symmetric string cosmological model for Takabayasi string i.e. ρ=(1+ω)λ does not exist in Barber’s second self creation theory. Further it is found that the string cosmological model in this theory exist only when ω=0. Therefore model for ρ=λ (geometric string) is constructed. Some physical and geometrical properties of the model are discussed.  相似文献   

18.
The Evans wave equation [1-3] is developed in the weak-field limit to give the Poisson equation and an electrogravitic equation expressing the electric field strength E in terms of the acceleration g due to gravity and a fundamental scalar potential (0) with the units of volts (joules per coulomb). The electrogravitic equation shows that an electric field strength can be obtained from the acceleration due to gravity, which in general relativity is non-Euclidean spacetime. Therefore an electric field strength can be obtained, in theory, from scalar curvature R. This inference is supported by recent experimental data from the patented motionless electromagnetic generator [5].  相似文献   

19.
New classes of charged-source 5D GR (Kaluza-Klein) metrics are derived here. These metrics, unlike prior Kaluza-Klein metrics, are both off-diagonal (representing charged solutions), andx 5-dependent. The x 5-dependence, in particular, is important as modern 5D GR (Induced Matter) theory has abandoned the cylindrical restriction on the 5th dimension (requiring it be curled up very small), and, thus, allows the metric to have x 5-dependence. x 5-dependence, therefore, represents a hitherto untapped potential for 5D GR investigation.  相似文献   

20.
In this paper, the fractional-order model is used to study dust acoustic rogue waves in dusty plasma. Firstly, based on control equations, the multi-scale analysis and reduced perturbation method are used to derive the (3+1)-dimensional modified Kadomtsev-Petviashvili (MKP) equation. Secondly, using the semi-inverse method and the fractional variation principle, the (3+1)-dimensional time-fractional modified Kadomtsev-Petviashvili (TF-MKP) equation is derived. Then, the Riemann-Liouville fractional derivative is used to study the symmetric property and conservation laws of the (3+1)-dimensional TF-MKP equation. Finally, the exact solution of the (3+1)-dimensional TF-MKP equation is obtained by using fractional order transformations and the definition and properties of Bell polynomials. Based on the obtained solution, we analyze and discuss dust acoustic rogue waves in dusty plasma.  相似文献   

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