Noether定理与黑洞的质量公式及黑洞熵

运用并发展了协变相空间的Noether荷方法,对于真空广义相对论稳态轴对称黑洞得到:黑洞质量公式是关于Killing向量场和完整Cauchy面上的零Noether荷以及黑洞力学第一定律.对于一大类向量场,利用零标架方法证明在视界附近的约化代数的中心项为零.这表明,Carlip用纯粹对称性分析的方法来解释黑洞熵的微观起源值得商榷.     

Spacetime Non-Commutativity Corrections to the Cardy-Verlinde Formula of Achúcarro-Ortiz Black Hole

In this letter we compute the corrections to the Cardy-Verlinde formula of Achúcarro-Ortiz black hole, which is the most general two-dimensional black hole derived from the three-dimensional rotating Banados-Teitelboim-Zanelli black hole. These corrections stem from the space non-commutativity. We show that in non-commutative case, non-rotating Achúcarro-Ortiz black hole in contrast with commutative case has two horizons.     

Hawking Tunneling Radiation of a Particle with Electric and Magnetic Charge from Kerr-Newman-Kasuya Black Hole

Extending the Parikh＇s quantum tunneling method of an uncharged particle, we investigate the quantum radiation characteristics of a particle with electric and magnetic charge via tunneling from the event horizon of the Kerr-Newman Kasuya black hole. The derived result supports the Parikh＇s opinion and the correction to the thermal spectrum is of precisely the form that satisfies the underlying unitary quantum theory, and finally provides a might explanation to the black hole information puzzle.     

Spherical Photon Orbits Around a Kerr Black Hole

Two circular photon orbits are known to exist in the equatorial plane of the Kerr black hole. In this paper, we investigate so-called spherical photon orbits—orbits with constant coordinate radii that are not confined to the equatorial plane. A one-parameter class of solutions is found, which includes the circular orbits as special cases. The properties of these spherical orbits are then analyzed, with the aim of classifying them by qualitative differences in their behavior. Finally, representative orbits from each class are plotted out, including a zero-angular momentum photon orbit and one with non-fixed azimuthal direction.     

Entropy of a Uniformly Accelerating Black Hole

Kinnersley has discussed the space–time of an arbitrarily accelerating point mass. We select a simple case in which the black hole is uniformly accelerated and the mass does not vary with time. We adopt thin film brick-wall model to calculate the entropy of black hole. We find that both the temperature and the entropy density of black hole can be calculated at every point on the horizon. This result indicates that the conclusion that black hole entropy is proportional to its area can be applied to horizon not only globally, but also locally.     

What Can the Quantum Liquid Say on the Brane Black Hole, the Entropy of an Extremal Black Hole, and the Vacuum Energy?

Using quantum liquids one can simulate the behavior of the quantum vacuum in the presence of the event horizon. The condensed matter analogs demonstrate that in most cases the quantum vacuum resists formation of the horizon, and even if the horizon is formed different types of the vacuum instability develop, which are faster than the process of Hawking radiation. Nevertheless, it is possible to create the horizon on the quantum-liquid analog of the brane, where the vacuum life-time is long enough to consider the horizon as the quasistationary object. Using this analogy we calculate the Bekenstein entropy of the near-extremal and extremal black holes, which comes from the fermionic microstates in the region of the horizon—the fermion zero modes. We also discuss how the cancellation of the large cosmological constant follows from the thermodynamics of the vacuum.     

Tunneling from a Quantum Black Hole

A quantum black hole has been presented by Kenmoku et al. (1998), and its surface gravity is divergent. We find that its tunneling probability is essentially different from Boltzmann distribution. It is interesting that two peaks appears in the spectrum when the black hole mass decreases close to Planck mass, which is different from black body radiation. PACS: 04.70.Dy     

Black Hole Radiation and Volume Statistical Entropy

The simplest possible equation for Hawking radiation and other black hole radiated power is derived in terms of black hole density, ρ . Black hole density also leads to the simplest possible model of a gas of elementary constituents confined inside a gravitational bottle of Schwarzchild radius at tremendous pressure, which yields identically the same functional dependence as the traditional black hole entropy S _bh∝ (kAc ³)/ℏ G. Variations of S _bh can be obtained which depend on the occupancy of phase space cells. A relation is derived between the constituent momenta and the black hole radius R _H, p = which is similar tothe Compton wavelength relation.     

Tunneling Radiation of a Torus-Like Black Hole in Anti-de Sitter Space-Time

An extension of the Parikh-Wilczek's semi-classical quantum tunneling method, the tunneling radiation of the charged particle from a torus-like black hole is investigated. Difference from the uncharged mass-less particle, the geodesics of the charged massive particle tunneling from the black hole is not light-like, but determined by the phase velocity. The derived result shows that the tunneling rate depends on the emitted particle's energy and electric charge, and takes the same functional form as uncharged particle. It proves also that the exact emission spectrum is not strictly pure thermal, but is consistent with the underlying unitary theory. PACS Numbers: 04.70.Dy, 97.60.Lf, 05.30.Ch.     

Dynamics of Particles Around a Regular Black Hole with Nonlinear Electrodynamics

We investigate the dynamics of a charged particle being kicked off from its circular orbit around a regular black hole by an incoming massive particle in the presence of magnetic field. The resulting escape velocity, escape energy and the effective potential are analyzed. It is shown that the presence of even a very weak magnetic field helps the charged particles in escaping the gravitational field of the black hole. Moreover the effective force acting on the particle visibly reduces with distance. Thus particle near the black hole will experience higher effective force as compared to when it is far away.     

Effects of Lorentz Breaking on the Accretion onto a Schwarzschild-like Black Hole

We formulate and solve the problem of spherically symmetric, steady state, adiabatic accretion onto a Schwarzschild-like black hole obtained recently. We derive the general analytic expressions for the critical points, the critical velocity, the critical speed of sound, and subsequently the mass accretion rate. The case for polytropic gas is discussed in detail. We find the parameter characterizing the breaking of Lorentz symmetry will slow down the mass accretion rate, while has no effect on the gas compression and the temperature profile below the critical radius and at the event horizon.     

Tunneling Radiation of the Charged Particles for Charged Spherical Black Hole in VGM

Applying Parikh’s semi-classical tunneling method, Hawking radiation of charged massive particles via tunneling from charged spherical black hole in vacuum for Vector Graviton Metric theory (VGM) of gravitation is investigated. Because the derivation respects conservation of energy and charge, the tunneling rate of particles is relevant to the change of Bekenstein-Hawking entropy and the exact spectrum is not precisely thermal. The result employs an underlying unitary theory. PACS numbers: 04.70.-s, 97.60. Lf     

相对论力学系统的形式不变性与Noether对称性

研究相对论力学系统的形式不变性与Noether对称性，给出相对论力学系统的Noether定理， 以及形式不变性的定义、判据和守恒量，得到形式不变性和Noether对称性的关系，并举例 说明结果的应用- 关键词： 相对论 力学系统 形式不变性 Noether对称性     

Bergmann-Thomson Energy of a Charged Rotating Black Hole

We obtain the energy distribution associated with a charged rotating (Kerr-Newman) black hole in Bergmann-Thomson formulation. We find that the energy-momentum definitions prescribed by Einstein, Landau-Lifshitz, Papapetrou, Weinberg, and Bergmann-Thomson give the same and acceptable result and also support the Cooperstock hypothesis for energy localization in general relativity. The repulsive effect due to the electric charge and rotation parameters of the metric is also reflected from the energy distribution expression.     

Spin of the M87 Black Hole

Spin measurement of the 6.5 billion solar mass black hole in M87 from the Event Horizon Telescope image is the latest in a series that span a wide range in values, but that tend to share the feature of corotation between the accretion flow and black hole. The spin paradigm for black holes predicts very high black hole spin which in that framework is produced in its last significant merger. High black hole spin appears to be ruled out in the gap paradigm, however, which predicts early formation with a mass already in excess of 4 billion solar masses. In this picture, the black hole experiences slow evolution as it departs from its original radio quasar phase and over billions of years not only fails to double its mass but also falls short of regaining its original high spin, such that it is now compatible with a corotating accreting black hole whose dimensionless spin fits best in the range 0.2 < a < 0.5.     

Letter: Gravitational Thermodynamics of a Vaidya Black Hole

The path integral approach is applied to the statistical thermodynamics of a radiating Vaidya black hole. The entropy still satisfies the Bekenstein-Hawking formula, except for a negligible term. The entropy production, as a measurement of the irreversibility, is also obtained.     

Comments on the Statistical Origin of Black Hole Entropy

This paper shows that the black hole entropy can be interpreted as emerging as a result of missing information about the exact state of the matter from which the black hole was formed.     

Addendum: Hawking Radiation of Photons in a Variable-Mass Kerr Black Hole

Hawking evaporation of photons in a variable-mass Kerr space-time is investigated by using a method of the generalized tortoise coordinate transformation. The blackbody radiant spectrum of photons displays a new spin-rotation coupling effect obviously dependent on different helicity states of photons.     

黑洞阴影在SSD中的位置和形状

假设旋转的黑洞在标准吸积盘内,在吸积盘的内边界等于最后稳定轨道的情况下,画出黑洞阴影在吸积盘的图像.通过定性和定量分析黑洞的形状和位置,发现对于相同质量的黑洞,黑洞阴影的大小及形状与黑洞的自旋参量有关.旋转黑洞阴影的形状和位置与它的旋转轴是不对称的,通过研究旋转轴与黑洞阴影的位置关系来确定黑洞的质量中心的位置及黑洞的旋转参量.     

Entropy of N-Dimensional Spherically Symmetric Charged Black Hole

By using the method of quantum statistics, we derive directly the partition functions of bosonic andfermionic fields in the N-dimensional spherically symmetric charged black hole space-time. The statistical entropy ofblack hole is obtained by an improved brick-wall method. When we choose proper parameters in our results, we canobtain that the entropy of black hole is proportional to the area of horizon. In our result, there do not exist neglectedterm and divergent logarithmic term given in the original brick-wall method. We avoid the difficulty in solving the waveequation of scalar and Dirac fields. We offer a simple and direct way of studying entropy of the higher-dimensional black hole.