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1.
Ding-Xiong Wang 《General Relativity and Gravitation》2000,32(4):553-563
Evolution characters of angular velocity H of a Kerr black hole (BH) and distribution characters of angular velocity
p
of accreting particles near the BH horizon are investigated in the case of thin and thick disks, respectively. It is shown that H evolves in a non-monotonous way in the case of thin-disk-pure-accretion, attaining a maximum at a
* 0.994. This evolution character turns out to depend on the radial gradient of
p
near the BH horizon. It is proved that both quantities, ( dH
/dt)
ms and (
p
/r)r=r
H, vanish at the same value of a
*: a
*0.994, and an explanation for the non-monotonousness of H is provided. 相似文献
2.
3.
Yuan K. Ha 《General Relativity and Gravitation》2003,35(11):2045-2050
An exact energy expression for a physical black hole is derived by considering the escape of a photon from the black hole. The mass of the black hole within its horizon is found to be twice its mass as observed at infinity. This result is important in understanding gravitational waves in black hole collisions. 相似文献
4.
S. S. Xulu 《Foundations of Physics Letters》2006,19(6):603-609
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. 相似文献
5.
In this paper, we consider the Casimir energy of massless scalar fields which satisfy the Dirichlet boundary condition on a spherical shell. Outside the shell, the spacetime is assumed to be described by the Schwarzschild metric, while inside the shell it is taken to be the flat Minkowski space. Using zeta function regularization and heat kernel coefficients we isolate the divergent contributions of the Casimir energy inside and outside the shell, then using the renormalization procedure of the bag model the divergent parts are cancelled, finally obtaining a renormalized expression for the total Casimir energy. 相似文献
6.
An analytical expression for the jet power extracted from the plunging region between a black hole (BH)horizon and the inner edge of the disk (hereafter the PL power) is derived based on an improved equivalent circuit in BH magnetosphere with a mapping relation between the radial coordinate of the plunging region and that of the remote astrophysical load.It is shown that the PL power is of great importance in explaining jet power and dominates over the BZ and DL powers for a wide value range of the BH spin.In addition,we show that the PL power derived in our model can be fitted with the strong jet powers of several 3CR FR I radio galaxies,which cannot be explained by virtue of the BZ mechanism.Furthermore,the condition for negative energy of the accreting particles in the plunging region is discussed with the validity of the second law of BH thermodynamics. 相似文献
7.
By using the solution describing a black hole embedded in the FLRW universe, we obtain the evolving equation of the black hole mass expressed in terms of the cosmological parameters. The evolving equation indicates that in the phantom dark energy universe the black hole mass becomes zero before the Big Rip is reached. 相似文献
8.
Two new mapping relations between the angular coordinate on the black hole (BH) horizon and radialcoordinate on the disc are given according to the requirement of general relativity and Maxwell‘s equations, and theeffects of magnetic coupling (MC) on temperature of accretion disc are investigated by comparing with pure accretion.It is shown that the MC effects on the temperature profile are related intimately to the BH spin, and the influenceon the peak value of disc temperature based on the modified mapping relations is not as great as that based on thelinear mapping.The peak value and the corresponding radius of peak value ring of disc temperature do not increasemonotonically as the increasing spin of BH, each containing a maximum for the fast-spinning BH. The value ranges ofthe bolometric luminosity and color temperature of the disc are both extended by the MC effects. 相似文献
9.
The Schwarzschild solution has played a fundamental conceptual role in general relativity, and beyond, for instance, regarding
event horizons, spacetime singularities and aspects of quantum field theory in curved spacetimes. However, one still encounters
the existence of misconceptions and a certain ambiguity inherent in the Schwarzschild solution in the literature. By taking
into account the point of view of an observer in the interior of the event horizon, one verifies that new conceptual difficulties
arise. In this work, besides providing a very brief pedagogical review, we further analyze the interior Schwarzschild black
hole solution. Firstly, by deducing the interior metric by considering time-dependent metric coefficients, the interior region
is analyzed without the prejudices inherited from the exterior geometry. We also pay close attention to several respective
cosmological interpretations, and briefly address some of the difficulties associated to spacetime singularities. Secondly,
we deduce the conserved quantities of null and timelike geodesics, and discuss several particular cases in some detail. Thirdly,
we examine the Eddington–Finkelstein and Kruskal coordinates directly from the interior solution. In concluding, it is important
to emphasize that the interior structure of realistic black holes has not been satisfactorily determined, and is still open
to considerable debate. 相似文献
10.
We consider the most general static spherically symmetric black hole metric. The accretion of the fluid flow around the Van der Waal's black hole is investigated and we calculate the fluid's four-velocity, the critical point and the speed of sound during the accretion process. We also analyze the nature of the universe's density and the mass of the black hole during accretion of the fluid flow. The density of the fluid flow is also taken into account. We observe that the mass is related to redshift. We compare the accreting power of the Van der Waal's black hole with Schwarzschild black hole for different accreting fluid. 相似文献
11.
Bo-Bo Wang 《General Relativity and Gravitation》2004,36(4):735-745
Using the thin film brick-wall model, the entropies of a toroidal black hole due to scalar and Dirac fields are investigated. The entropy due to the scalar field is one fourth of the horizon area, and that due to the Dirac field is seven eighth of the area. These results are similar to that in black holes with horizon topology S
2. The cutoff in toroidal black hole is chosen as the same as one in black holes with horizon topology S
2, which seems to mean that the thin film brick-wall model is universal. 相似文献
12.
I-Ching Yang Chi-Long Lin Irina Radinschi 《International Journal of Theoretical Physics》2009,48(1):248-255
According to the Einstein, Weinberg, and M?ller energy-momentum complexes, we evaluate the energy distribution of the singularity-free
solution of the Einstein field equations coupled to a suitable nonlinear electrodynamics suggested by Ayón-Beato and García.
The results show that the energy associated with the definitions of Einstein and Weinberg are the same, but M?ller not. Using
the power series expansion, we find out that the first two terms in the expression are the same as the energy distributions
of the Reissner-Nordstr?m solution, and the third term could be used to survey the factualness between numerous solutions
of the Einstein field equations coupled to a nonlinear electrodynamics. 相似文献
13.
F. Finster N. Kamran J. Smoller S. -T. Yau 《Communications in Mathematical Physics》2009,287(3):829-847
The Cauchy problem is considered for the scalar wave equation in the Kerr geometry. We prove that by choosing a suitable wave
packet as initial data, one can extract energy from the black hole, thereby putting supperradiance, the wave analogue of the
Penrose process, into a rigorous mathematical framework. We quantify the maximal energy gain. We also compute the infinitesimal
change of mass and angular momentum of the black hole, in agreement with Christodoulou’s result for the Penrose process. The
main mathematical tool is our previously derived integral representation of the wave propagator.
Research supported in part by the Deutsche Forschungsgemeinschaft.
Research supported by NSERC grant # RGPIN 105490-2004.
Research supported in part by the Humboldt Foundation and the National Science Foundation, Grant No. DMS-0603754.
Research supported in part by the NSF, Grant No. 33-585-7510-2-30. 相似文献
14.
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. 相似文献
15.
A. López-Ortega 《General Relativity and Gravitation》2003,35(1):59-68
Using the Newman-Penrose formalism and the brick wall model the entropy of a Kerr black hole due to a massless Rarita–Schwinger field is calculated. The dependence of the subleading correction with the spin is analyzed and the differences with previously published results are discussed. 相似文献
16.
You-Gen Shen 《General Relativity and Gravitation》2000,32(8):1647-1660
The expression of Fermionic entropy is derived in Garfinkle-Horne dilaton black hole background, by using 't Hooft's brick wall model and Newman-Penrose's spinor analysis approach. 相似文献
17.
In this paper, by using quantum statistical method, we obtain the partition function of Bose field and Fermi field on the background of the 5-dimensional rotating black hole. Then via the improved brick-wall method and membrane model, we calculate the entropy of Bose field and Fermi field of the black hole. And it is obtained that the entropy of the black hole is not only related to the area of the outer horizon but also is the function of inner horizon‘s area. In our results, there are not the left out term and the divergent logarithmic term in the original brick-wall method.The doubt that why the entropy of the scalar or Dirac field outside the event horizon is the entropy of the black hole in the original brick-wall method does not exist. The influence of spinning degeneracy of particles on entropy of the black hole is also given. It is shown that the entropy determined by the areas of the inner and outer horizons will approach zero,when the radiation temperature of the black hole approaches absolute zero. It satisfies Nernst theorem. The entropy can be taken as the Planck absolute entropy. We provide a way to study higher dimensional black hole. 相似文献
18.
19.
Recent research shows that Hawking radiation from black hole horizon can be treated as a quantum tunneling process, and fermions tunneling method can successfully recover Hawking temperature. In this tunneling framework, choosing a set of appropriate matrices γ^μ is an important technique for fermions tunneling method. In this paper, motivated by Kerner and Man's fermions tunneling method of 4 dimension black holes, we further improve the analysis to investigate Hawking tunneling radiation from a rotating charged black hole in 5-dimensional gauged supergravity by constructing a set of appropriate matrices γ^μ for general covariant Dirac equation. Finally, the expected Hawking temperature of the black hole is correctly recovered, which takes the same form as that obtained by other methods. This method is universal, and can also be directly extend to the other different-type 5-dimensional charged black holes. 相似文献
20.
ZHAORen WUYue-Qin ZHANGLi-Chun 《理论物理通讯》2003,40(6):745-748
In this paper, by using quantum statistical method, we obtain the partition function of Bose field and Fermi field on the background of the 5-dimensional rotating black hole. Then via the improved brick-wall method and membrane model, we calculate the entropy of Bose field and Fermi field of the black hole. And it is obtained that the entropy of the black hole is not only related to the area of the outer horizon but also is the function of inner horizon‘s area. In our results, there are not the left out term and the divergent logarithmic term in the original brick-wall method.The doubt that why the entropy of the scalar or Dirac field outside the event horizon is the entropy of the black hole in the original brick-wall method does not exist. The influence of spinning degeneracy of particles on entropy of the black hole is also given. It is shown that the entropy determined by the areas of the inner and outer horizons will approach zero,when the radiation temperature of the black hole approaches absolute zero. It satisfies Nernst theorem. The entropy can be taken as the Planck absolute entropy. We provide a way to study higher dimensional black hole. 相似文献