Generalized uncertainty principle and s-wave semiclassical tunneling radiation of Kerr black hole

Based on the generalized uncertainty principle, the modified area and entropy of Kerr black hole is calculated. The semiclassical Parikh-Wilczeck tunneling proposal is applied to a Kerr horizon. It is shown that the tunneling radiation probability of Kerr black hole is modified.     

Effect of holographic principle and generalized uncertainty principle on the semiclassical Parikh-Wilczek tunneling radiation of black holes

In the present paper, based on the generalized uncertainty principle, the Parikh-Wilczek black hole tunneling radiation is studied. It is shown that the black hole tunneling radiation receives a correction. Furthermore a bound on the tunneling approach, is shown to be valid when, based on the holographic principle, a bound applied to the black hole entropy.     

Generalized uncertainty principle and Bekenstein-Hawking entropy in tunneling rate of Kerr black hole

We study the effects of the generalized uncertainty principle in the tunneling formalism for Hawking radiation to evaluate the quantum-corrected Hawking temperature and entropy for a Kerr black hole. By assumption of a spatially flat universe accompanied with expansion of metric, the modified area and entropy of Kerr black hole are calculated and we could obtain an expression for entropy of black hole that is changing with respect to time and Bekenstein-Hawking temperature.     

Hawking radiation and entropy of Kerr-Newman black hole

The entropy correction of Kerr-Newman black hole is investigated using the Hamilton-Jacobi method beyond semiclassical approximation. To get entropy correction, the inverse of the sum of square of event horizon (r ₊) and the square of rotational parameter a of the black hole is taken as the proportionality parameter for quantum corrections of the action I _i to the semiclassical action I ₀. It has been shown that as quantum effects are taken into account the corrections to the Bekenstein-Hawking entropy of the stationary black hole include a logarithmic term and an inverse area term beyond the semiclassical approximation.     

Hawking radiation from a dielectric black hole

Using the new global embedding approach and analytical continuation method of wave function we discuss Hawking radiation of acoustic black holes. Unruh/Hawking temperature of the dielectric black hole is derived. The corresponding relation among these methods that calculate Hawking radiation of dielectric black hole is established. Our result shows that these methods are equivalent.     

Magnetic fields and quasi-periodic oscillations of black hole radiation

Various relations are found between the key parameters of black holes and active galactic nuclei. Some have a statistical property, others follow from the theoretical consideration of the evolution of these objects. In this paper we use a recently discovered empirical relation between the characteristic frequency of quasi-periodic oscillations of radiation ν _br of black holes, their masses and matter accretion rates to determine the magnetic field strength B _H at the black hole event horizon. Since the characteristic frequency can be determined from observations, the use of a new relation for the estimations of magnetic field B _H can yield more definite results, since we are decreasing the number of the unknown or poorly-determined parameters of objects (it especially concerns the accretion rate Ṁ). The typical values which we have found are B _H ≃ 10⁸G for the stellar mass black holes, and B _H ≃ 10⁴G for the supermassive black holes. Besides, we demonstrate that if the linear polarization of an object is caused by the radiation of a magnetized accretion disk, then the degree of observable polarization is p ∼ ν _br ^−1/2.     

Hawking radiation and thermodynamics of a Vaidya-Bonner black hole

Using Parikh’s tunneling method,the Hawking radiation on the apparent horizon of a Vaidya-Bonner black hole is calculated.When the back-reaction of particles is neglected,the thermal spectrum can be precisely obtained.Then,the black hole thermodynamics can be calculated successfully on the apparent horizon.When a relativistic perturbation is applied to the apparent horizon,a similar calculation can also lead to a purely thermal spectrum.The first law of thermodynamics can also be derived successfully at the...     

Cosmic microwave background radiation of black hole universe

Modifying slightly the big bang theory, the author has recently developed a new cosmological model called black hole universe. This new cosmological model is consistent with the Mach principle, Einsteinian general theory of relativity, and observations of the universe. The origin, structure, evolution, and expansion of the black hole universe have been presented in the recent sequence of American Astronomical Society (AAS) meetings and published recently in a scientific journal: Progress in Physics. This paper explains the observed 2.725 K cosmic microwave background radiation of the black hole universe, which grew from a star-like black hole with several solar masses through a supermassive black hole with billions of solar masses to the present universe with hundred billion-trillions of solar masses. According to the black hole universe model, the observed cosmic microwave background radiation can be explained as the black body radiation of the black hole universe, which can be considered as an ideal black body. When a hot and dense star-like black hole accretes its ambient materials and merges with other black holes, it expands and cools down. A governing equation that expresses the possible thermal history of the black hole universe is derived from the Planck law of black body radiation and radiation energy conservation. The result obtained by solving the governing equation indicates that the radiation temperature of the present universe can be ∼2.725 K if the universe originated from a hot star-like black hole, and is therefore consistent with the observation of the cosmic microwave background radiation. A smaller or younger black hole universe usually cools down faster. The characteristics of the original star-like or supermassive black hole are not critical to the physical properties of the black hole universe at present, because matter and radiation are mainly from the outside space, i.e., the mother universe.     

Back reaction and Hawking radiation from a Vaidya black hole

Using Damour-Ruffini’s and Hamilton-Jacobi’s methods, Hawking radiation from a Vaidya black hole is investigated. Due to non-stationary black holes, the event horizon r _H and the entropy S are all related to both the mass m(υ) and . When the back-reaction of particles’s energy to space-time is considered, we get the emission probability. It is found that the result is different from that of the stationary Schwarzschild black hole, because is the function of mass m(υ).      

Quantum tunneling makes a Reissner–Nordstrom black hole turn into a Kerr–Newman black hole under angular momentum conservation

Hawking radiation can be viewed as a process of particle quantum tunneling near a black hole horizon. When a particle with angular momentum tunnels across the event horizon of a Reissner–Nordstrom black hole, the black hole will change into a Kerr–Newman one. In previous papers, axisymmetric black hole has been studied only when a keeps constant. Changing from Reissner–Nordstrom to Kerr–Newman should be a simple case when a varies. After this, more general radiation including changed a in Kerr or Kerr–Newman spacetimes can be studied in the future. The emission rate of the massless particles with angular momentum is calculated, and the result is consistent with an underlying unitary theory.      

The generalized uncertainty principle and the thermodynamic quantities near a black hole

The continuous complex Morlet wavelet transform is used to investigate temporal rotation cycle length of daily sunspot areas from May 9, 1874 to February 28, 2010, from a global point of view. The rotation cycle length of the Sun is found to have a secular trend: it decreased from the year of 1874 to 1950s, and since then the Sun is rotating more and more speedily in the long run. The rotation period appears around the maximum times of the Schwabe cycles with statistical significance, but in the minimum times it is always statistically insignificant, although it is found to have no relation with the Schwabe cycle. The period length of the rotation cycle displays the significant periods of 2.61 and 5.77 years.     

Hawking radiation of Dirac particles via tunneling from a black plane

Extending Kerner and Mann’s fermion tunneling, we investigate the Dirac particle’s tunneling radiation from a black plane in Anti-de Sitter space-time. The result shows that the tunneling probability is related to the change of Bekenstein-Hawking entropy.     

Hawking radiation of Kerr-Newman black hole in different tortoise coordinate transformations

Hawking radiation effect of Maxwell’s electromagnetic fields in the Kerr-Newman black hole space-time is investigated using two different tortoise coordinate transformations. It has been shown that the new tortoise coordinate transformation produces constant term ξ in the expression of surface gravity and Hawking temperature. If ξ is set to zero, the surface gravity and Hawking temperature will be equal to those obtained from the old tortoise coordinate transformation. This indicates that new transformation is more reliable and accurate. The black body radiant spectrum of photon displays a new spin-rotation coupling effect.     

Gravitational radiation from a particle falling into a Kerr black hole

The gravitational radiation from a highly relativistic test particle spiralling inward toward a Kerr black hole along a conical surface is estimated. The spectra of several lowest multipoles depending on the polar angle of the falling particle at infinity are obtained for the frequency band c ³ GM^–1.     

Low-frequency radiation from a particle falling into a Kerr black hole

In this paper we consider the low-frequency limit of the electromagnetic and gravitational radiation from a relativistic particle falling into a Kerr black hole. The radiation spectra are obtained with help of the solution of Teukolsky's equations in terms of the hypergeometric functions. It is shown that in the low-frequency limit the spectra are flat and the power radiated depends strongly on the radiation spin. Dependence of the power on the initial kinetic energy of the radiating particle has the same character as that obtained by the WKB technique for the band of frequencies , where 0=(1–u ₀ ² /c ²)^–1/2 is the particle Lorentz factor at infinity. The full energy radiated is proportional to 0 in 0 for electromagnetic radiation and to ₀ ³ for gravitational radiation.     

High-frequency radiation from a particle falling into a Kerr black hole

The high-frequency electromagnetic and gravitational radiation from a relativistic particle falling into a Kerr and Schwarzschild black hole is considered. The spectral and angular distributions of the radiation power are calculated by the WKB technique to Teukolsky's equations. The spectra obtained have a characteristic exponential cut-off at the frequency = _char. which is proportional to the particle Lorentz factor =(1–v ²/c²)^–1/2. At the frequencies as low as those compared with _char. both electromagnetic and gravitational spectra are flat. The amount of the energy emitted in the low-frequency modes of the radiation depends strongly on the radiation spin. It is proportional to ln for the electromagnetic and to ³ for the gravitational radiation.     

Back reaction and quantum gravity corrections of Hawking radiation from Schwarzschild-de Sitter black hole

Following the Parikh and Wilczek semiclassical tunneling method of massless particle, hawking radiation of Schwarzschild-de Sitter (SdS) black hole have been computed using null geodesic method. Purely thermal and quantum gravity corrections have been made and have shown that both the corrections give the same results and all the tunneling rates are related to change of Bekenstein-Hawking entropy of SdS black hole. The results obtained for SdS black hole are also in accordance with Parikh and Wilczek’s opinion and gives a correction to the Hawking radiation of SdS black hole.     

Reversible-process black hole thermodynamics

Bekenstein, Hawking, Gibbons and Perry have discussed the case of placing a Schwarzschild black hole inside an ideal, reflecting box, thereby setting up an equilibrium state. In this paper, we discuss more generally the thennodynamical properties of such a system. Starting from adiabatic expansion of the system, we are naturally led to the definition of total entropy and of black hole entropy. We next point out the two conditions for stable equilibrium between the black hole and the radiation, V < V_E and E_r < M/4 are not equivalent: only the former is necessary and sufficient. Lastly, we examine three quasi-static processes of evaporation of the black hole, expansion at constant energy, energy release at constant volume and adiabatic expansion.