Quantum radiation of non-stationary Kerr-Newman-de Sitter black hole

By introducing a new tortoise coordinate transformation, we investigate the quantum thermal and non-thermal radiations of a non-stationary Kerr-Newman-de Sitter black hole. The accurate location and radiate temperature of the event horizon as well as the maximum energy of the non-thermal radiation are derived. It is shown that the radiate temperature and the maximum energy are related to not only the evaporation rate, but also the shape of the event horizon, moreover the maximum energy depends on the electromagnetic potential. Finally, we use the results to reduce the non-stationary Kerr-Newman black hole, the non-stationary Kerr black hole, the stationary Kerr-Newman-de Sitter black hole, and the static Schwarzshild black hole.

The quantum tunnelling radiation of Schwarzschild de Sitter black hole with a global monopole

Applying Parikh＇s quantum tunnelling method, this paper has studied the quantum tunnelling radiation of Schwarzschild de Sitter black hole with a global monopole. The result shows that the tunnelling rates at the event horizon and the cosmological horizon are related to Bekenstein-Hawking entropy and the derived radiation spectrum is not precisely thermal when considering energy conservation and self-gravitation interaction.

A new method of researching fermion tunneling from the Vaidya-Bonner de Sitter black hole

Using the general tortoise coordinate transformation, we research the fermion tunneling of the Vaidya-Bonner de Sitter black hole via a semi-classical method and finally obtain the right surface gravity, Hawking temperature and tunneling rate near the event horizon and cosmical horizon.

Quantum Tunneling Radiation of Reissner-Nordstrom de Sitter Black Hole with a Global Monopole

Applying Parikh＇s quantum tunneling model, we study the quantum tunneling radiation of Reissne- Nordstrom de Sitter black hole with a global monopole. The result shows that the tunneling rates at the event horizon and the cosmic horizon are related to Bekenstein-Hawking entropy if we take the energy conservation into consideration, and the true radiate spectrum is not precisely thermal.

对高维Schwarzschild-de Sitter黑洞视界处Fermions量子隧穿辐射率的修正

根据Lorentz-breaking理论对弦量场作用量进行修正并应用变分原理得到了高维Schwarzschild-de Sitter黑洞时空中的费米子动力学方程。通过对此动力学方程的研究得到了高维Schwarzschild-de Sitter黑洞事件视界处和宇宙视界处的量子隧穿率的修正形式,从而研究了此黑洞事件视界处和宇宙视界处的修正形式的Hawking温度和Bekenstein-Hawking熵的新的表达式。在得到研究结果的基础之上,文中最后还对研究方法和结论进行了讨论。

Quantization of Horizon Area of Kerr–Newman–de Sitter Black Hole

Using the adiabatic invariant action and applying the Bohr–Sommerfeld quantization rule and first law of black hole thermodynamics, a study of the quantization of the entropy and horizon area of a Kerr–Newman–de Sitter black hole is carried out. The same entropy spectrum is obtained in two different coordinate systems. It is also observed that the spacing of the entropy spectrum is independent of the black hole parameters. Also, the corresponding quantum of horizon area is in agreement with the results of Bekenstein.

Hawking radiation from the dilaton-(anti) de Sitter black hole via covariant anomaly

Adopting the anomaly cancellation method, initiated by Robinson and Wilczek recently, this paper discusses Hawking radiation from the dilaton-（anti） de Sitter black hole. To save the underlying gauge and general covariance, it introduces covariant fluxes of gauge and energy-momentum tensor to cancel the gauge and gravitational anomalies. The result shows that the introduced compensating fluxes are equivalent to those of a 2-dimensional blackbody radiation at Hawking temperature with appropriate chemical potential.

Hawking radiation of stationary and non-stationary Kerr–de Sitter black holes

Hawking radiation of the stationary Kerr–de Sitter black hole is investigated using the relativistic Hamilton–Jacobi method. Meanwhile, extending this work to a non-stationary black hole using Dirac equations and generalized tortoise coordinate transformation, we derived the locations, the temperature of the thermal radiation as well as the maximum energy of the non-thermal radiation. It is found that the surface gravity and the Hawking temperature depend on both time and different angles. An extra coupling effect is obtained in the thermal radiation spectrum of Dirac particles which is absent from thermal radiation of scalar particles. Further, the chemical potential derived from the thermal radiation spectrum of scalar particle has been found to be equal to the highest energy of the negative energy state of the scalar particle in the non-thermal radiation for the Kerr–de Sitter black hole. It is also shown that for stationary black hole space time, these two different methods give the same Hawking radiation temperature.

Covariant Anomaly and Hawking Radiation from Kerr-Newman Black Hole in Dragging Coordinates Frame

In the light of Robinson and Wilczek's new idea,and motivated by Banerjee and Kulkarni's simplified method of using only the covariant anomaly to derive Hawking radiation from a black hole,we generally extend the work to Kerr-Newman black hole in dragging coordinates frame.It is shown that the flows introduced to cancel the anomaly at the event horizon are equal to the corresponding Hawking radiation in dragging coordinates frame,which supports and extends Robinson and Wilczek's opinion.

Hawking Radiation from Horizons of Reissner-Nordstrm de Sitter Black Hole with a Global Monopole via Anomalies

Hawking radiation from cosmological horizon and event horizon of the Reissner-Nordstrom de Sitter black hole with a global monopole is studied via a new method that was propounded by Robinson and Wilzek and elaborated by Banerjee and Kulkarni. The results show that the gauge current and energy-momentum tensor fluxes, which required keeping gauge covariance and general coordinate invariance at the quantum level in the effective field theory, are exactly equivalent to those of Hawking radiation from the event horizon and the cosmological horizon, respectively.

Thermodynamics of DBI Black Holes in Anti-de Sitter Spacetime

Through the gauge field theory, we obtain the solution of the DBI-AdS black hole, In the meantime, according to the relations between the action and the grand partition function, we obtain the grand partition function in the DBI-AdS black hole. The temperature and the potential of the DBI-AdS black hole are gained from differential of the grand partition function. With the thermodynamic relations, other thermodynamics are also obtained. The solution and the thermodynamics of the DBI-AdS black hole are turned out that they can reduce to the case of a charged black hole in four-dimensional spacetimes.

Dilaton Black Hole Tunneling Radiation in de Sitter Universe

The Hawking radiation via tunneling from the dilaton black hole in de Sitter universe is investigated using Parikh Wilczek＇s method. We show that if the self-gravitational interaction and energy conservation are taken into account, the modified radiation spectrum deviates from exact thermal spectrum and satisfies the unitary theory.

Thermodynamic properties of Reissner-Nordstrm-de Sitter quintessence black holes

The mass,electric charge,and temperature of black holes in the Reissner-Nordstrm-de Sitter quintessence（RN-dSQ） spacetime are obtained.The heat capacities of the RN-dSQ black holes for certain electric charges and masses are analyzed.The electrostatic energy and dark energy in the RN-dSQ black holes are also calculated.

The Correct Reissner-Nordstrøm, Kerr and Kerr-Newman Metrics

In a very recent article of mine I have corrected the traditional derivation of the Schwarzschild metric thus arriving to formulate a correct Schwarzschild metric different from the traditional Schwarzschild metric. In this article, starting from this correct Schwarzschild metric, I also propose corrections to the other traditional Reissner-Nordstrøm, Kerr and Kerr-Newman metrics on the basis of the fact that these metrics should be equal to the correct Schwarzschild metric in the borderline case in which they reduce to the case described by this metric. In this way, we see that, like the correct Schwarzschild metric, also the correct Reissner-Nordstrøm, Kerr and Kerr-Newman metrics do not present any event horizon (and therefore do not present any black hole) unlike the traditional Reissner-Nordstrøm, Kerr and Kerr-Newman metrics.

磁荷对Hayward-Anti-de Sitter黑洞的全息互信息的影响

Hayward黑洞是爱因斯坦引力非线性耦合一个携带磁荷的电磁场的解析解,是非线性磁单极子引力场的简并结构。一般情况下,黑洞的内部会存在奇点,而“非奇异”黑洞是一种内部没有奇点的黑洞。Hayward黑洞属于非奇异黑洞,此规则黑洞的对称性由磁势决定,带磁荷和不带磁荷的黑洞具有不同的微观结构。利用纠缠熵讨论磁荷对非奇异Hayward-Anti-de Sitter黑洞中全息互信息的影响。结果表明,随着条带宽度(子区域)的增加,2个渐进子系统纠缠增大,且全息互信息随磁荷的增加而降低。除此之外,存在临界磁荷使得全息互信息为零,此时对偶的子区域之间不存在纠缠,磁荷取不同值时,全息互信息消失的条带宽度临界值是不同的。

Generated genuine tripartite steering and its monogamy in the background of a Kerr-Newman black hole

We study the redistribution of quantum steering and its monogamy in the presence of a four-dimensional Kerr-Newman black hole.The gravitational effect of the Kerr-Newman black hole is shown to generate genuine tripartite steering between causally disconnected regions,depending on the polar angle,angular momentum,electric charge,and magnetic charge of the black hole.We obtain strong evidence of steering monogamy,that is,the"sudden death"of the A→B steering results in the"sudden birth"of B→B steering.We also obtain the condition of maximal steering asymmetry,that is,η0=√1+tanh^(2)(s),revealing the transition between two-way and one-way steering in Kerr-Newman spacetime.

A simpler method for researching fermions tunneling from black holes

A new simpler mathematic method is proposed to study fermions tunneling from black holes. According to this method, by using semiclassical approximation theory, it simplifies the Dirac equation of curved spacetime and then the relationship of the gamma matrix and the component of contravariant metric is considered in order to transform the set of difficult quantum equations into a simple equation. Finally, the fermion tunneling and Hawking radiation of black holes are obtained. The method is very effective and simple, and we will take the Schwarzschild black hole with global monopole and the higher-dimensional Reissner-Nordstrom de Sitter black hole as two examples to show the fact.

The Singularities of Gravitational Fields of Static Thin Loop and Double Spheres Reveal the Impossibility of Singularity Black Holes

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.

Motion of a Test Particle in the Kerr-Newman De/Anti De Sitter Space-Time

In this paper we obtain the geodesic equations of motion of a test particle (charged particle and photon) in the Kerr-Newman de/anti de Sitter black hole by using the Hamilton-Jacobi equation. We determine the positions of the inner, outer and cosmological horizons of the black hole. In terms of the effective potentials, the trajectory of the test particle within the inner horizon is studied. It appears that there are stable circular orbits of a charged particle and photon within the inner horizon and that the combined effect of the charge and rotation of the Kerr-Newman de/anti de Sitter black hole and the coupling between the charge of the test particle and the electromagnetic field of the black hole may account for this.

de Sitter时空背景下的熵

从deSitter时空背景下的Klein Gordon方程出发 ,利用brick wall方法计算了宇宙的自由能和熵 .结果表明 ,宇宙的熵与Schwarzschild黑洞一样 ,也为视界面积的 1/ 4 .可见 ,brick wall方法具有更广泛的适用性 ,不但可以计算黑洞的熵 ,而且可以计算宇宙的熵 .