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1.
A solution of Einstein’s vacuum field equations that describes a boosted Kerr black hole relative to an asymptotic Lorentz frame at future null infinity is derived. The solution has three parameters (mass, rotation and boost) and corresponds to the most general configuration that an astrophysical black hole must have; it reduces to the Kerr solution when the boost parameter is zero. In this solution the ergosphere is north-south asymmetric, with dominant lobes in the direction opposite to the boost. However the event horizon, the Cauchy horizon and the ring singularity—which are the core of the black hole structure—do not alter, being independent of the boost parameter. Possible consequences for astrophysical processes connected with Penrose processes in the asymmetric ergosphere are discussed.  相似文献   

2.
It is shown that right and left combinations of the positive-and negative-frequency hyperbolically symmetric solutions of the Klein-Fock-Gordon equation possess an everywhere timelike current density vector with a definite Lorentz-invariant sign of the charge density, and similar combinations of solutions to the Dirac equation possess the energy-momentum tensor with everywhere real eigenvalues and a definite Lorentz-invariant sign of the energy density. These right and left modes, just as their ±-frequency components, are eigenfunctions of the Lorentz boost generator with the eigenvalue к. The sign of the charge (energy) density coincides with the sign of к for the right scalar (spinor) modes and is opposite to it for the left modes. It is then reasonable to assume that the particles (antiparticles) are precisely described by the right modes with к>0(к<0) and by the left modes with к<0(к>0).  相似文献   

3.
The Lorentz boost is derived from the Evans wave equation of generally covariant unified field theory by constructing the Dirac spinor from the tetrad in the SU(2) representation space of non-Euclidean spacetime. The Dirac equation in its wave formulation is then deduced as a well-defined limit of the Evans wave equation. By factorizing the dAlembertian operator into Dirac matrices, the Dirac equation in its original first differential form is obtained from the Evans wave equation. Finally, the Lorentz boost is deduced from the Dirac equation using geometrical arguments. A self-consistency check of the Evans wave equation is therefore forged by deducing therefrom the Lorentz boost in the appropriate limit. This procedure demonstrates that the Evans wave equation governs the properties of matter and anti-matter in general relativity and unified field theory and leads both to Fermi-Dirac and Bose-Einstein statistics in general relativity.  相似文献   

4.
通过耦合迭代求解流体力学方程和电磁场方程,数值模拟了转移式自由燃烧电弧和具有细长中间段及突扩阳极结构的壁稳式非转移直流电弧的流场,分析了洛伦兹力对这两种典型直流电弧流场的影响。结果显示:在自由燃烧电弧情况下,电流自感磁场的洛伦兹力对流场特性有显著影响,自磁压缩是约束电弧的主要机制;而在壁稳式非转移直流电弧情况下,相对于强壁面约束和气动力作用而言,洛伦兹力对流场的影响有限。特别在中间段出口以后,洛伦兹力与气动力的比值小于0.010,因此,当主要考虑壁稳式非转移直流电弧发生器出口参数时,为了提高数值模拟效率,可忽略洛伦兹力的作用。  相似文献   

5.
Two-forms in Minkowski space-time may be considered as generators of Lorentz transformations. Here, the covariant and general expression for the composition law (Baker–Campbell–Hausdorff formula) of two Lorentz transformations in terms of their generators is obtained. For simplicity, the expression is first obtained for complex generators, then translated to real ones. Every generator has two essential eigenvalues and two invariant (two–)planes; the eigenvalues and the invariant planes of the Baker–Campbell–Hausdorff composition of two generators are also obtained.  相似文献   

6.
The classical relativistic theory is developed of electric and magnetic fields in terms of boost and rotation generators, respectively, of the Lorentz group of space-time. This development shows that Minkowski geometry requires that there be threestates of polarization of radiation in free space. The magnetic components in a circular basis are right and left circular and longitudinal. The longitudinal component is real and physical, and proportional to one of the three, nonzero, rotation generators of the Lorentz group. The longitudinal electric component is pure imaginary, and proportional to one of the three boost generators. These theoretical arguments conform with experimental data from the Planck radiation law and from magnetic effects of light such as the inverse Faraday effect.  相似文献   

7.
Most of previous work on applying the conformal group to quantum fields has emphasized its invariant aspects, whereas in this paper we find that the conformal group can give us running quantum fields, with some constants, vertex and Green functions running, compatible with the scaling properties of renormalization group method(RGM). We start with the renormalization group equation(RGE), in which the differential operator happens to be a generator of the conformal group, named dilatation operator. In addition we link the operator/spatial representation and unitary/spinor representation of the conformal group by inquiring a conformal-invariant interaction vertex mimicking the similar process of Lorentz transformation applied to Dirac equation. By this kind of application,we find out that quite a few interaction vertices are separately invariant under certain transformations(generators) of the conformal group. The significance of these transformations and vertices is explained. Using a particular generator of the conformal group, we suggest a new equation analogous to RGE which may lead a system to evolve from asymptotic regime to nonperturbative regime, in contrast to the effect of the conventional RGE from nonperturbative regime to asymptotic regime.  相似文献   

8.
A search for an annual variation of a daily sidereal modulation of the frequency difference between colocated 129Xe and 3He Zeeman masers sets a stringent limit on boost-dependent Lorentz and CPT violation involving the neutron, consistent with no effect at the level of 150 nHz. In the framework of the general standard-model extension, the present result provides the first clean test for the fermion sector of the symmetry of spacetime under boost transformations at a level of 10(-27) GeV.  相似文献   

9.
The thermodynamic interaction at thermodynamic equilibrium in the free fermion gas is described in an alternative way by the coupling of particles with a scalar thermodynamic field that features self-interaction. This alternative coupling is similar to the Higgs coupling and is helpful in understanding the temperature transformation at thermodynamic equilibrium under the Lorentz boost. As this coupling is applied in the abelian interaction fermion gas, nothing nontrivial is obtained. However, an interesting thing happens in the nonabelian interaction fermion gas where the difference appears for the diagonal and off-diagonal intermediate bosons as the Higgs-like coupling is added.  相似文献   

10.
Two dimensional calculations were carried out to clarify the behavior of boundary layer and its effects on performance of closed cycle MHD (CCMHD) generator and to investigate the relation between enthalpy extraction ratio and adiabatic efficiency. Calculation results suggest that the large Lorentz force causes propagation and separation of boundary layer where reverse current flows, because of small electromotive force. For large load resistance boundary layer becomes very thick and the eddy current arises in broad region. The push work of working gas against Lorentz force is effectively converted into electric energy under the condition at which the Lorentz force decelerates the working gas to Mach number in the range between 1.0 and 1.5 in this case of the generator. Stagnation pressure loss increases with load resistance until enthalpy extraction ratio takes maximum value. The entropy production due to Joule heating and viscosity increases with load resistance. The difference between the load resistances for which the enthalpy extraction ratio and the adiabatic efficiency take maximum value can be explained with the entropy production of Joule heating and viscosity  相似文献   

11.
魏文叶  申佳音  吴奕暐  杨礼想  薛迅  阮自强 《物理学报》2017,66(13):130301-130301
微波背景辐射的低l极矩的各向异性可能不能用微波背景辐射静止系boost到本动参考系来解释,我们推断boost对称性在宇宙学尺度上缺失,又由于单纯结合广义相对论和物质结构的标准模型不能解释星系以上尺度的引力现象,需要引入暗物质和暗能量.而迄今为止所有寻找暗物质粒子的实验给出的都是否定结果,暗能量的本质更是一个谜.因此,我们假设洛伦兹对称性是从星系以上尺度开始部分破缺,以非常狭义相对论对称群E(2)为例,用E(2)规范理论来构造大尺度有效引力理论,并分析了此规范理论的自洽性.从这些讨论中发现,当物质源即使为普通标量物质时,contortion也一般非零,非零contortion的存在会贡献一个等效能量动量张量的分布,它可能对暗物质效应给出至少部分的贡献.我们从对称性出发修改引力,有别于其他的修改引力理论.  相似文献   

12.
In this paper we postulate an algebraic model to relate the triplet characteristic of lepton families to Lorentz violation. Inspired by the two-to-one mapping between the group SL(2, C) and the Lorentz group via the Pauli grading (the elements of SL(2, C) expressed by direct sum of unit matrix and generators of SU (2) group), we grade the SL(3, C) group with the generators of SU(3), i. e. the Gell-Mann matrices, then express the SU(3) group in terms of three SU(2) subgroups, each of which stands for a lepton species and is mapped into the proper Lorentz group as in the case of the group SL(2,C). If the mapping from group SL(3,C) to the Lorentz group is constructed by choosing one SU(2) subgroup as basis, then the other two subgroups display their impact only by one more additional generator to that of the original Lorentz group. Applying the mapping result to the Dirac equation, it is found that only when the kinetic vertex γμξμ is extended to encompass γμξμ can the Dirac-equation-form be conserved. The generalized vertex is useful in producing neutrino oscillations and mass differences.  相似文献   

13.
We propose a modification of special relativity in which a physical energy, which may be the Planck energy, joins the speed of light as an invariant, in spite of a complete relativity of inertial frames and agreement with Einstein's theory at low energies. This is accomplished by a nonlinear modification of the action of the Lorentz group on momentum space, generated by adding a dilatation to each boost in such a way that the Planck energy remains invariant. The associated algebra has unmodified structure constants. We also discuss the resulting modifications of field theory and suggest a modification of the equivalence principle which determines how the new theory is embedded in general relativity.  相似文献   

14.
通过求解带电粒子在均匀电场中与坐标系选取无关的三维矢量相对论运动方程,进而利用洛伦兹变换方法,求得了带电粒子在E2>H2的均匀正交电磁场中相对论运动轨迹的一般三维矢量式.并使用Mathematica软件在直角坐标系中描绘了相应的粒子相对论运动轨迹图.  相似文献   

15.
Novel electric field effects on Landau levels in graphene   总被引:1,自引:0,他引:1  
A new effect in graphene in the presence of crossed uniform electric and magnetic fields is predicted. Landau levels are shown to be modified in an unexpected fashion by the electric field, leading to a collapse of the spectrum, when the value of electric to magnetic field ratio exceeds a certain critical value. Our theoretical results, strikingly different from the standard 2D electron gas, are explained using a "Lorentz boost," and as an "instability of a relativistic quantum field vacuum." It is a remarkable case of emergent relativistic type phenomena in nonrelativistic graphene. We also discuss few possible experimental consequence.  相似文献   

16.
宁成  丁宁  杨震华 《物理学报》2007,56(1):338-345
从原子的电离能和维持等离子体所需能量出发,给出了估算任一元素材料,要产生任一壳层的X射线辐射,每个离子(原子)所需要的基本能量和要达到的内爆箍缩速度的方法.对“强光一号”加速器上典型的氪喷气和部分钨丝阵Z箍缩实验的电流和电压波形所蕴涵的丰富物理信息进行了分析,得到了电感和洛伦兹(Lorentz)力做功等物理量的变化规律以及负载参数变化对它们的影响.该电感与基于壳层模型计算出的电感有较大的差异.前者随箍缩开始而缓慢增大,甚至在箍缩到心和飞散后还在增大,最后大致稳定在100 nH附近.差异可能是由于壳层模型过于简化和电流电压的测点同负载有一定的距离而造成的.当丝阵直径为8 mm时,洛伦兹力做功最大;当丝阵直径相同时,丝数较大时,洛伦兹力做功也较大.同时还对该加速器的喷气和丝阵负载的线质量进行了优化,表明也是直径为8 mm的钨丝阵为最佳负载,这同实验的优化结果也一致.  相似文献   

17.
Wigner’s little groups are the subgroups of the Poincaré group whose transformations leave the four-momentum of a given particle invariant. For a relativistic particle in motion the little group is a boosted rotation. On the other hand, the kinematical effect of two non-colinear Lorentz boosts is another boost preceded or follwed by a rotation, which is called the Wigner rotation. It is shown that there is always a Wigner rotation for a given little group rotation. The differences between those two rotations are clearly demonstrated and some interesting physical applications are presented.  相似文献   

18.
In quantum relativistic Hamiltonian dynamics, the time evolution of interacting particles is described by the Hamiltonian with an interaction-dependent term (potential energy). Boost operators are responsible for (Lorentz) transformations of observables between different moving inertial frames of reference. Relativistic invariance requires that interaction-dependent terms (potential boosts) are present also in the boost operators and therefore Lorentz transformations depend on the interaction acting in the system. This fact is ignored in special relativity, which postulates the universality of Lorentz transformations and their independence of interactions. Taking into account potential boosts in Lorentz transformations allows us to resolve the no-interaction paradox formulated by Currie, Jordan, and Sudarshan [Rev. Mod. Phys. 35, 350 (1963)] and to predict a number of potentially observable effects contradicting special relativity. In particular, we demonstrate that the longitudinal electric field (Coulomb potential) of a moving charge propagates instantaneously. We show that this effect as well as superluminal spreading of localized particle states is in full agreement with causality in all inertial frames of reference. Formulas relating time and position of events in interacting systems reduce to the usual Lorentz transformations only in the classical limit (0) and for weak interactions. Therefore, the concept of Minkowski space-time is just an approximation which should be avoided in rigorous theoretical constructions.  相似文献   

19.
The isoscalar giant monopole and quadrupole states in finite nuclei are studied in a relativistic δ-ω model by making use of a local Lorentz boost and scaling method, and the nuclear surface and the density distribution are treated in the relativistic Thomas-Fekmi approximation.The excitation energies of the giant resonances are self-consistently calculated. It is found that the excitation energies of giant monopole arehbasically in agreement with experimental data for all nuclei and those of giant quadrupole for light nuclei. Coupling constants and δ-meson mass in the theory are chosen to fit static properties of nuclear matter.  相似文献   

20.
周国泉 《中国物理 B》2009,18(7):2779-2784
This paper introduces Lorentz beams to describe certain laser sources that produce highly divergent fields. The fractional Fourier transform (FRFT) is applied to treat the propagation of Lorentz beams. Based on the definition of convolution and the convolution theorem of the Fourier transform, an analytical expression for a Lorentz beam passing through a FRFT system has been derived. By using the derived formula, the properties of a Lorentz beam in the FRFT plane are illustrated numerically.  相似文献   

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