Modified Hawking Temperature Research Articles

Black hole remnant and quantum tunnelling in three-dimensional Gödel spacetime

Using the modified Dirac equation in a three-dimensional gravity background, we investigate the quantum correction to tunnelling radiation from a Godel black hole, and discuss the black hole remnant employing fermion’s tunnelling. The corrected tunnelling probability is derived, and the modified Hawking temperature is found as well. It is worth emphasizing that, only when the condition j>αω(3r −−r +) is satisfied, emitting both a mass particle and a massless particle, the remnant of the Godel black hole may arise.

Corrected Fermions’ Tunnelling from a Black Plane with Effects of Quantum Gravity

Using the modified Dirac equation in curved spacetime based on the generalized uncertainty principle, we investigate the quantum tunnelling of fermionic particle and discuss on the remnants of a black plane, which is an exact solution to Einstein field equation in four dimensional theory of gravity with a negative cosmological constant. The corrected tunnelling probability is derived, and the modified Hawking temperature is found as well. The result shows that the quantum gravity correction slows down the increase of the temperature during the emission and the black hole evaporation terminates at remnant mass.

Generalized Bekenstein–Hawking system: logarithmic correction

The present work is a generalization of the recent work [ arXiv.1206.1420 ] on the modified Hawking temperature on the event horizon. Here the Hawking temperature is generalized by multiplying the modified Hawking temperature by a variable parameter $$\alpha $$ representing the ratio of the growth rate of the apparent horizon to that of event horizon. It is found that both the first and the generalized second law of thermodynamics are valid on the event horizon for any fluid distribution. Subsequently, the Bekenstein entropy is modified on the event horizon and the thermodynamical laws are examined. Finally, an interpretation of the parameters involved is presented.

Quantum Tunnelling for Hawking Radiation from Both Static and Dynamic Black Holes

The paper deals with Hawking radiation from both a general static black hole and a nonstatic spherically symmetric black hole. In case of static black hole, tunnelling of nonzero mass particles is considered and due to complicated calculations, quantum corrections are calculated only up to the first order. The results are compared with those for massless particles near the horizon. On the other hand, for dynamical black hole, quantum corrections are incorporated using the Hamilton-Jacobi method beyond semiclassical approximation. It is found that different order correction terms satisfy identical differential equation and are solved by a typical technique. Finally, using the law of black hole mechanics, a general modified form of the black hole entropy is obtained considering modified Hawking temperature.

Corrected Entropy of a General Spherically Symmetric Black Hole

Adopting the tortoise coordinates transformation in the advanced Eddington coordinates and applying the generalized law of thermodynamics, we discuss the corrected entropy of a general spherically symmetric black hole beyond the semi-classical limit. We give the corrections to the Bekenstein-Hawking area law following from the modified Hawking temperature. Two examples are explicitly worked out. The conclusion is that the corrected entropy includes a logarithmically term and an inverse term to the Bekenstein-Hawking entropy, which is the same form as that of the static and the stationary black holes discussed by using the loop quantum gravity and the string theory.

Tunneling of massive particles from noncommutative inspired Schwarzschild black hole

We apply the generalization of the Parikh-Wilczek method to the tunneling of massive particles from noncommutative inspired Schwarzschild black holes. By deriving the equation of radial motion of the tunneling particle directly, we calculate the emission rate which is shown to be dependent on the noncommutative parameter besides the energy and mass of the tunneling particle. After equating the emission rate to the Boltzmann factor, we obtain the modified Hawking temperature which relates to the noncommutativity and recovers the standard Hawking temperature in the commutative limit. We also discuss the entropy of the noncommutative inspired Schwarzschild black hole and its difference after and before a massive particle's emission.

Quantum tunneling beyond semiclassical approximation

Hawking radiation as tunneling by Hamilton-Jacobi method beyond semiclassical approximation is analysed. We compute all quantum corrections in the single particle action revealing that these are proportional to the usual semiclassical contribution. We show that a simple choice of the proportionality constants reproduces the one loop back reaction effect in the spacetime, found by conformal field theory methods, which modifies the Hawking temperature of the black hole. Using the law of black hole mechanics we give the corrections to the Bekenstein-Hawking area law following from the modified Hawking temperature. Some examples are explicitly worked out.

Black hole remnants and dark matter

We argue that, when the gravity effect is included, the generalized uncertainty principle (CUP) may prevent black holes from total evaporation in a similar way that the standard uncertainty principle prevents the hydrogen atom from total collapse. Specifically we invoke the GUP to obtain a modified Hawking temperature, which indicates that there should exist non-radiating remnants (BHR) of about Planck mass. BHRs are an attractive candidate for cold dark matter. We investigate an alternative cosmology in which primordial BHRs are the primary source of dark matter.

Baryogenesis from primordial black holes after the electroweak phase transition

Incorporating a realistic model for accretion of ultrarelativistic particles by primordial black holes (PBHs), we study the evolution of an Einstein--de Sitter universe consisting of PBHs embedded in a thermal bath from the epoch $\ensuremath{\sim}{10}^{\ensuremath{-}33}\mathrm{sec}$ to $\ensuremath{\sim}5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}9}\mathrm{sec}.$ In this paper we use the ansatz of Barrow et al. to model black hole evaporation in which the modified Hawking temperature goes to zero in the limit of the black hole attaining a relic state with a mass $\ensuremath{\sim}{m}_{\mathrm{Pl}}.$ Both the single mass PBH case as well as the case in which black hole masses are distributed in the range $8\ifmmode\times\else\texttimes\fi{}{10}^{2}--3\ifmmode\times\else\texttimes\fi{}{10}^{5}\mathrm{g}$ have been considered in our analysis. Black holes with a mass larger than $\ensuremath{\sim}{10}^{5}\mathrm{g}$ appear to survive beyond the electroweak phase transition and, therefore, successfully manage to create baryon excess via $X\ensuremath{-}\overline{X}$ emissions, averting the baryon number washout due to sphalerons. In this scenario, we find that the contribution to the baryon-to-entropy ratio by PBHs of initial mass m is given by $\ensuremath{\sim}\ensuremath{\epsilon}\ensuremath{\zeta}(m/1\mathrm{g}{)}^{\ensuremath{-}1},$ where \ensuremath{\epsilon} and \ensuremath{\zeta} are the CP-violating parameter and the initial mass fraction of the PBHs, respectively. For \ensuremath{\epsilon} larger than $\ensuremath{\sim}{10}^{\ensuremath{-}4},$ the observed matter-antimatter asymmetry in the universe can be attributed to the evaporation of PBHs.