利用新的整体嵌入方法研究高维旋转黑洞的Hawking效应和Unruh效应

首先通过维数约化的方法,在事件视界附近将高维旋转时空线元化为二维度规(仅仅是(t－r)部分),然后利用新的整体嵌入方法研究了(1+1)维时空的Hawking温度(Unruh温度).研究结果验证了Banerjee和Majhi观点的正确性,同时将该观点推广到了高维旋转黑洞的研究,得到了高维旋转黑洞的Hawking 温度(Unruh温度). 关键词： 黑洞 高维旋转 Hawking效应 Unruh效应     

Fermion tunneling from a non-static black hole with the internal global monopole

Kerner and Mann’s recent research shows that the Hawking temperature and tunneling rate can be obtained by the fermion tunneling method from the Rindler space-time and a general non-rotating black hole. In this paper, considering the tunneling particles with spin 1/2 and taking into account the particle’s self-gravitation in the dynamical background space-time, we further improve Kerner and Man’s fermion tunneling method to investigate Hawking radiation via tunneling from a non-static black hole with the internal global monopole. The result shows that the tunneling rate of the non-static black hole is related to the integral of the changing horizon besides the change of Bekenstein–Hawking entropy, which is different from the stationary cases. It also essentially implies that the unitary is violated for the reason that the black hole is non-stationary and cannot be treated as an isolated system.     

Holographic dilatonic dark energy model

In this paper, we apply the quantum anomaly cancelation method and the effective action approach as well as the method of Damour–Ruffini–Sannan to derive Hawking radiation of Dirac particles from the Myers–Perry black hole. Using the dimensional reduction technique, we find that the fermionic field in the background of the Myers–Perry black hole can be treated as an infinite collection of quantum fields in (1+1)-dimensional background coupled with the dilaton field and the U(1) gauge field near the horizon. Thus Hawking temperature and fluxes are found. The Hawking temperature obtained agrees with the surface gravity formula while the Hawking fluxes derived from the anomaly cancelation method and the effective action approach are in complete agreement with the ones obtained from integrating the Planck distribution.     

Hawking radiation from gravity''s rainbow via gravitational anomaly

Based on the anomaly cancellation method, initiated by Robinson and Wilczek, we investigates Hawking radiation from the modified Schwarzschild black hole from gravity＇s rainbow from the anomaly point of view. Unlike the general Schwarzschild space-time, the metric of this black hole depends on the energies of probes. The obtained result shows to restore the underlying general covariance at the quantum level in the effective field, the covariant compensating flux of energy-momentum tensor, which is related to the energies of the probes, should precisely equal to that of a （1 ＋ 1）-dimensional blackbody at the Hawking temperature.     

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

Hawking radiation from cosmological horizon and event horizon of the Reissner-Nordström 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.     

Scalar resonant frequencies and Hawking effect of an f(R) global monopole

Massive scalar fields are considered in the gravitational field produced by a Schwarzschild black hole with a global monopole in f(R) gravity.The exact solution of the radial part of the Klein-Gordon equation in this background is obtained and is given in terms of the general Heun functions.We apply the properties of the general Heun functions to study the Hawking radiation and the resonant frequencies of scalar particles.     

Formation of the remnant close to Planck scale and the Schwarzschild black hole with global monopole

In this paper, we use the generalized uncertainty principle (GUP) and quantum tunneling method to research the formation of the remnant from a Schwarzschild black hole with global monopole. Based on the corrected Hamilton–Jacobi equation, the corrections to the Hawking temperature, heat capacity and entropy are calculated. We not only find the remnant close to Planck scale by employing GUP, but also research the thermodynamic stability of the black hole remnant according to the phase transition and heat capacity.     

Relationship between Hawking radiation and gravitational anomalies

We show that in order to avoid a breakdown of general covariance at the quantum level the total flux in each outgoing partial wave of a quantum field in a black hole background must be equal to that of a (1+1)-dimensional blackbody at the Hawking temperature.     

Charged Fermions Tunneling from a Rotating Charged Black Hole in 5-Dimensional Gauged Supergravity

Recent research shows that Hawking radiation from black hole horizoncan 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 byconstructing 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.     

Schwarzschild black hole with global monopole charge

We derive the metric for a Schwarzschild black hole with global monopole charge by relaxing asymptotic flatness of the Schwarzschild field. We then study the effect of global monopole charge on particle orbits and the Hawking radiation. It turns out that existence, boundedness and stability of circular orbits scale up by (1−8πη ²)⁻¹, and the perihelion shift and the light bending by (1−8πη ²)^−3/2, while the Hawking temperature scales down by (1−8πη ²)² the Schwarzschild values. Hereη is the global charge.     

Hawking Radiation from Horizons of Reissner-Nordstrom de Sitter Black Hole with a Giobal 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.     

Hawking Radiation from NUT Kerr Newman Kusuya Black Hole via Effective Action and Covariant Anomalies

Using the theory of the anomalous (chiral) effective action and covariant anomalies method, the Hawking radiation from NUT-Kerr-Newman-Kusuya black hole is researched. In this paper, the electric charge parameter and magnetic monopole parameter are rewritten as equivalent parameter. In addition, we simplify the metric as 1+1 dimensional effective metric. Finally, with the method of anomalous effective action and covariant anomalies respectively, we calculate the chiral covariant current and covariant energy-momentum tensor.     

Hawking radiation via tunnelling from black holes with topological defects

In this paper, we extend Parikh's recent work to two kinds of the black holes whose ADM mass is no longer identical to its mass parameter, each with a topological defect, one being a global monopole black hole and another a cosmic string black hole. We view Hawking radiation as a tunnelling process across the event horizon and calculate the tunnelling probability. From the tunnelling probability we also find a leading correction to the semiclassical emission rate. The results are consistent with an underlying unitary theory.     

Quantization of the space－time with topological defect

We present the classical solution of Lagrange equations for the black hole with a global monopole or with a cosmic string. Then we obtain the wavefunction of the space－time by solving the Wheeler－De Witt equation. De Broglie－Bohm interpretation applied to the wavefunction gives the quantum solution of the space－time. In the end, the quantum effect on Hawking radiation is studied.     

Thermodynamics of noncommutative geometry inspired black holes based on Maxwell-Boltzmann smeared mass distribution

In order to further explore the effects of non-Gaussian smeared mass distribution on the thermodynamical properties of noncommutative black holes, we consider noncommutative black holes based on Maxwell-Boltzmann smeared mass distribution in (2+1)-dimensional spacetime. The thermodynamical properties of the black holes are investigated, including Hawking temperature, heat capacity, entropy and free energy. We find that multiple black holes with the same temperature do not exist, while there exists a possible decay of the noncommutative black hole based on Maxwell-Boltzmann smeared mass distribution into the rotating (commutative) BTZ black hole.     

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.     

Entropy Evolution in the Interior Volume of a Charged $f(R)$ Black Hole *

Based on the 4-dimensional black hole solution of $f(R)$ theory coupled to a nonlinear Maxwell field, we calculate the interior volume of a charged $f(R)$ black hole using the method proposed by Christodoulou and Rovelli. Considering massless scalar field in the interior volume and Hawking radiation carrying only energy, we calculate the entropy of the scalar field inside a charged $f(R)$ black hole and investigate the evolution of the entropy under Hawking radiation. In the meantime, the evolution of the Bekenstein-Hawking entropy under Hawking radiation has also been calculated. Based on these results, the proportional relation is obtained between the evolution of the scalar field entropy and the evolution of Bekenstein-Hawking entropy under Hawking radiation. According to the result, we investigate and discuss how the modified coefficient $b$ in $f(R)$ gravity theory affects the evolution relation between the two types of entropy. It is shown that the radiation rate for Hawking radiation of a charged $f(R)$ black hole can increase with the modified coefficient $b$.     

Higher-dimensional black holes with Dirac–Born–Infeld (DBI) global defects

It is well-known that the exact solution of non-linear \(\sigma \) model coupled to gravity can be perceived as an exterior gravitational field of a global monopole. Here we study Einstein’s equations coupled to a non-linear \(\sigma \) model with Dirac–Born–Infeld (DBI) kinetic term in D dimensions. The solution describes a metric around a DBI global defects. When the core is smaller than its Schwarzschild radius it can be interpreted as a black hole having DBI scalar hair with deficit conical angle. The solutions exist for all D, but they can be expressed as polynomial functions in r only when D is even. We give conditions for the mass M and the scalar charge \(\eta \) in the extremal case. We also investigate the thermodynamic properties of the black holes in canonical ensemble. The monopole alter the stability differently in each dimensions. As the charge increases the black hole radiates more, in contrast to its counterpart with ordinary global defects where the Hawking temperature is minimum for critical \(\eta \). This behavior can also be observed for variation of DBI coupling, \(\beta \). As it gets stronger (\(\beta \ll 1\)) the temperature increases. By studying the heat capacity we can infer that there is no phase transition in asymptotically-flat spacetime. The AdS black holes, on the other hand, undergo a first-ordered phase transition in the Hawking–Page type. The increase of the DBI coupling renders the phase transition happen for larger radius.     

Hawking radiation from charged black holes via gauge and gravitational anomalies

Extending the method of Robinson and Wolczek, we show that in order to avoid a breakdown of general covariance and gauge invariance at the quantum level the total flux of charge and energy in each outgoing partial wave of a charged quantum field in a Reissner-Nordstr?m black hole background must be equal to that of a (1 + 1)-dimensional blackbody at the Hawking temperature with the appropriate chemical potential.