Hawking radiation from the Schwarzschild black hole with a global monopole via gravitational anomaly

This paper derives the Hawking flux from the Schwarzschild black hole with a global monopole by using Robinson and Wilczek＇s method. Adopting a dimensional reduction technique, it can describe the effective quantum field in the （3 ＋ 1）-dimensional global monopole background by an infinite collection of the （1 ＋ 1）-dimensional massless fields if neglecting the ingoing modes near the horizon, where the gravitational anomaly can be cancelled by the （1 ＋ 1）- dimensional black body radiation at the Hawking temperature.

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 via tunnelling from general stationary axisymmetric black holes

Hawking radiation is viewed as a tunnelling process. In this way the emission rates of massless particles and massive particles tunnelling across the event horizon of general stationary axisymmetric black holes are calculated, separately. The emission spectra of these two different kinds of outgoing particles have the same functional form and both are consistent with an underlying unitary theory.

Hawking radiation from Kerr-Newman de Sitter black hole via anomalies

In this paper, Hawking radiation from the Kerr Newman de Sitter black hole is studied via gauge anomaly and gravitational anomaly. The obtained results of Hawking radiation from the event horizon and the cosmological horizon accord with those by other methods.

Hawking radiation from the charged and magnetized BTZ black hole via covariant anomaly

This paper discusses Hawking radiation from the charged and magnetized Bafiados-Teitelboim-Zanelli （BTZ） black hole from the viewpoint of anomaly, initiated by Robinson and Wilczek recently. It reconstructs the electromagnetic field tensor and the Lagrangian of the field corresponding to the source with electric and magnetic charges to redefine an equivalent charge and gauge potential. It employs the covariant anomaly cancellation method to determine the compensating fluxes of charge flow and energy-momentum tensor, which are shown to match with those of the 2- dimensional blackbody radiation at the Hawking temperature exactly.

Non-equilibrium Landauer transport model for Hawking radiation from a Reissner-Nordstrom black hole

The recent work of Nation et al., in which the Hawking radiation energy and entropy flow from a black hole is considered to be produced in a one-dimensional Landauer transport process, is extended to the case of a Reissner- Nordstrom black hole. The energy flow contains not only the contribution of the thermal flux but also that of the particle flux. It is found that the charge can also be transported via the one-dimensional quantum tunnel. Because of the existence of the electrostatic potential, the entropy production rate is shown to be smaller than that of the Schwarzschild black hole.

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.

Hawking radiation from Kerr-Newman-Kasuya black hole via quantum anomalies

We have studied the Hawking radiation of the Kerr-Newman-Kasuya black hole via gauge and gravitational anomaly in the dragging coordinates. The fluxes of the electromagnetic current and the energy momentum tensor for each partial wave in two-dimensional field are obtained.

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.

On Hawking Radiation of 3D Rotating Hairy Black Holes

We study the Hawking radiation of 3D rotating hairy black holes. Specifically, we compute the transition probability of bosonic and fermionic particles in such backgrounds. Then, we show that the transition probability is independent of the nature of the particle. It is observed that the charge of the scalar hairy B and the rotation parameter a control such a probability.

Black Hole Entropy from Entropy of Hawking Radiation

We provide a simple way for calculating the entropy of a Schwarzschild black hole from the entropy of its Hawking radiation. To this end, we show that if a thermodynamic system loses its energy only through the black body radiation, its loss of entropy is always 3/4 of the entropy of the emitted radiation. This proposition enables us to relate the entropy of an evaporating black hole to the entropy of its Hawking radiation. Explicitly, by calculating the entropy of the Hawking radiation emitted in the full period of evaporation of the black hole, we find the Bekenstein-Hawking entropy of the initial black hole.

Hawking radiation from a Vaidya black hole by Hamilton-Jacobi method

Using the Hamilton Jacobi method, Hawking radiation from the apparent horizon of a dynamical Vaidya black hole is calculated. The black hole thermodynamics can be built successfully on the apparent horizon. If a relativistic perturbation is given to the apparent horizon, a similar calculation can also lead to a purely thermal spectrum, which corresponds to a modified temperature from the former. The first law of thermodynamics can also be constructed successfully at a new supersurface which has a small deviation from the apparent horizon. When the event horizon is thought as such a deviation from the apparent horizon, the expressions of the characteristic position and temperature are consistent with the previous result that asserts that thermodynamics should be built on the event horizon. It is concluded that the thermodynamics should be constructed on the apparent horizon exactly while the event horizon thermodynamics is just one of the perturbations near the apparent horizon.

Hawking radiation from a five-dimensional Lovelock black hole

We investigate Hawking radiation from a five-dimensional Lovelock black hole using the Hamilton- Jacobi method. The behavior of the rate of radiation is plotted for various values of tile ultraviolet correction parameter and the cosmological constant. The results show that, owing to the ultraviolet correction and the presence of dark energy represented by the cosmological constant, the black hole radiates at a slower rate in comparison to the case without ultraviolet correction or cosmological constant. Moreover, the presence of the cosmological constant makes the effect of the ultraviolet correction on the black hole radiation negligible.

Hawking radiation and page curves of the black holes in thermal environment

As realistic objects in the Universe,the black holes are surrounded by complex environment.By taking the effect of thermal environment into account,we investigate the evaporation process and the time evolutions(page curves)of the entanglement entropies of Hawking radiation of various types of black holes.It is found that the black holes with the thermal environments evaporate slower than those without the environments due to the environmental contribution of the energy flux in addition to Hawking radiation.For Schwarzschild black hole and Reissner-Nordstr?m black hole in flat spaces,when the initial temperature of the black hole is higher than the environment temperature,the black holes evaporate completely and the Hawking radiation is eventually purified.For Schwarzschild-Ad S black hole,it will evaporate completely and the Hawking radiation is purified when the environment temperature is lower than the critical temperature.Otherwise,it will reach an equilibrium state with the environment and the radiation is maximally entangled with the black hole.Our results indicate that the final state of the black hole is determined by the environmental temperature and the temporal evolution and the speed of the information purification process characterized by the page curve of the Hawking radiation is also influenced by the thermal environment significantly.

Non-thermal Hawking radiation from the Kerr black hole

We present a short and direct derivation of Hawking radiation by using the Damour-Ruffini method, as taking into account the self-gravitational interaction from the Kerr black hole. It is found that the radiation is not exactly thermal, and because the derivation obeys conservation laws, the non-thermal Hawking radiation can carry information from the black hole. So it can be used to explain the black hole information paradox, and the process satisfies unitary.

Hawking radiation received at infinity in higher dimensional Reissner-Nordstrom black hole spacetimes

In this study,we investigate the Hawking radiation in higher dimensional Reissner-Nordstrom black holes as received by an observer located at infinity.The frequency-dependent transmission rates,which deform the thermal radiation emitted in the vicinity of the black hole horizon,are evaluated numerically.In addition to those in four-dimensional spacetime,the calculations are extended to higher dimensional Reissner-Nordstrom metrics,and the results are observed to be sensitive to the spacetime dimension to an extent.Generally,we observe that the transmission coefficient practically vanishes when the frequency of the emitted particle approaches zero.It increases with frequency and eventually saturates to a certain value.For four-dimensional spacetime,the above result is demonstrated to be mostly independent of the metric's parameter and the orbital quantum number of the particle,when the location of the event horizon,rh,and the product of the charges of the black hole and the particle qQ are known.However,for higher-dimensional scenarios,the convergence becomes more gradual.Moreover,the difference between states with different orbital quantum numbers is observed to be more significant.As the magnitude of the product of charges qQ becomes more significant,the transmission coefficient exceeds 1.In other words,the resultant spectral flux is amplified,which results in an accelerated process of black hole evaporation.The relationship of the calculated outgoing transmission coefficient with existing results on the greybody factor is discussed.

On a Heuristic Viewpoint Concerning the Conversion and Transformation of Sound into Light

In the study of Terrestrial Gamma-ray Flashes (TGFs) and Sonoluminescence, we observe parallels with larger cosmic events. Specifically, sonoluminescence involves the rapid collapse of bubbles, which closely resembles gravitational collapse in space. This observation suggests the potential formation of low-density quantum black holes. These entities, which might be related to dark matter, are thought to experience a kind of transient evaporation similar to Hawking radiation seen in cosmic black holes. Consequently, sonoluminescence could be a valuable tool for investigating phenomena typically linked to cosmic scale events. Furthermore, the role of the Higgs boson is considered in this context, possibly connecting it to both TGFs and sonoluminescence. This research could enhance our understanding of the quantum mechanics of black holes and their relation to dark matter on Earth.

Kerr-Newman-Kasuya Black Hole Tunnelling Radiation

The radiation of black hole contributes to the shrinking of the event horizon such that the background spacetime should not be fixed. In this study we take into account the self-gravitation effect to study the radiation of Kerr Newman-Kasuya black hole as tunnelling. Using the facts of energy conservation and angular momentum conservation we derive the tunnelling rate and show that the spectrum of the radiation as tunnelling is not purely thermal.

Massive particle radiation from Gibbons Maeda black hole

This paper investigated the massive particle radiation from Gibbons-Maeda black hole by using a semi-classical method. The calculations showed that, if the self-gravitation of the radiated particle is taken into account, the radiation spectrum deviates from exact black body spectrum and the rate of tunneling equals precisely the exponent of the difference of the black hole entropies before and after emission. The conclusion supports the viewpoint of information conservation.

Quantum Radiation of a Non-stationary Kerr-Newman Black Hole in de Sitter Space-Time

Hawking radiation of Klein-Gordon and Dirac particles in a non-stationary Kerr-Newman-de-Sitter black hole is studied by introducing a new tortoise coordinate transformation. The result shows that the Fermi-Dirac radiant spectrum displays a new term that represents the interaction between the spin of spinor particles and the rotation of black holes, which is absent in the Bose-Einstein distribution of Klein-Gordon particles.