Thermodynamics of five-dimensional static three-charge STU black holes with squashed horizons

We present a new expression for the five-dimensional static Kaluza-Klein black hole solution with squashed $S^3$ horizons and three different charge parameters. This black hole solution belongs to $D = 5$ $N = 2$ supergravity theory, its spacetime is locally asymptotically flat and has a spatial infinity $R times S^1 hookrightarrow S^2$. The form of the solution is extraordinary simple and permits us very conveniently to calculate its conserved charges by using the counterterm method. It is further shown that our thermodynamical quantities perfectly obey both the differential and the integral first laws of black hole thermodynamics if the length of the compact extra-dimension can be viewed as a thermodynamical variable.

A note on black hole spectroscopy in the tunneling mechanism

The paper has been withdrawn by the author.

On black hole spectroscopy via quantum tunneling

In recent work [emph{Quantum tunneling and black hole spectroscopy, Phys. Lett.} B686 (2010) 279, arXiv:0907.4271, by Banerjee et al.], it has been shown, in the tunneling mechanism, the area spacing parameter of a black hole horizon is given by $gamma=4$. In this paper, by carefully analyzing the tunneling process of the black hole radiation, we interestingly find that the most qualified candidate for a universal area gap in the tunneling mechanism is $gamma=8pi$. First, we develop the Banerjees treatment and the Kunstatters conjecture to revisit the black hole spectroscopy via quantum tunneling, and find for a real tunneling process, the area spacing parameter is given by the possible value $gammageq 4$. That is, the previous model-dependent area spacing parameters, i.e. $gamma=8pi, 4ln 3, 4$, are all possible in the tunneling mechanism. Finally, some discussions are followed to find, in the tunneling mechanism, $gamma=8pi$ is the most qualified candidate for a universal area spacing parameter.

Revisit emission spectrum and entropy quantum of the Reissner-Nordstr{o}m black hole

Banerjee and Majhis recent work shows that black holes emission spectrum could be fully reproduced in the tunneling picture, where, as an intriguing technique, the Kruskal extension was introduced to connect the left and right modes inside and outside the horizon. Some attempt, as an extension, was focused on producing the Hawking emission spectrum of the (charged) Reissner-Nordstr{o}m black hole in the Banerjee-Majhis treatment. Unfortunately, the Kruskal extension in their observation was so badly defined that the ingoing mode was classically forbidden traveling towards the center of black hole, but could quantum tunnel across the horizon with the probability $Gamma=e^{-pi omega_0/kappa_+}$. This tunneling picture is unphysical. With this point as a central motivation, in this paper we first introduce such a suitable Kruskal extension for the (charged) Reissner-Nordstr{o}m black hole that a perfect tunneling picture can be provided during the charged particles emission. Then, under the new Kruskal extension, we revisit the Hawking emission spectrum and entropy spectroscopy as tunneling from the charged black hole. The result shows that the tunneling method is so universally robust that the Hawking blackbody emission spectrum from a charged black hole can be well reproduced in the tunneling mechanism, and its induced entropy quantum is a much better approximation for the forthcoming quantum gravity theory.

Fermions tunnelling from the charged dilatonic black holes

Kerner and Manns recent work shows that, for an uncharged and non-rotating black hole, its Hawking temperature can be exactly derived by fermions tunnelling from its horizons. In this paper, our main work is to improve the analysis to deal with charged fermion tunnelling from the general dilatonic black holes, specifically including the charged, spherically symmetric dilatonic black hole, the rotating Einstein-Maxwell-Dilaton-Axion (EMDA) black hole and the rotating Kaluza-Klein (KK) black hole. As a result, the correct Hawking temperatures are well recovered by charged fermions tunnelling from these black holes.

Hawking radiation of Dirac particles via tunnelling from rotating black holes in de Sitter spaces

Hawking radiation from black hole horizon can be viewed as a quantum tunnelling process, and fermions via tunnelling can successfully recover Hawking temperature. In this paper, considering the tunnelling particles with spin 1/2 (namely, Dirac particles), we further improve Kerner and Mans fermion tunnelling method to study Hawking radiation via tunnelling from rotating black holes in de Sitter spaces, specifically including that from Kerr de Sitter black hole and Kerr-Newman de Sitter black hole. As a result, Hawking temperatures at the event horizon (EH) and the cosmological horizon (CH) are well described via Dirac particles tunnelling.

Anomalies and de Sitter radiation from the generic black holes in de Sitter spaces

Robinson-Wilczeks recent work shows that, the energy momentum tensor flux required to cancel gravitational anomaly at the event horizon of a Schwarzschild-type black hole has an equivalent form to that of a (1+1)-dimensional blackbody radiation at the Hawking temperature. Motivated by their work, Hawking radiation from the cosmological horizons of the general Schwarzschild-de Sitter and Kerr-de Sitter black holes, has been studied by the method of anomaly cancellation. The result shows that the absorbing gauge current and energy momentum tensor fluxes required to cancel gauge and gravitational anomalies at the cosmological horizon are precisely equal to those of Hawking radiation from it. It should be emphasized that the effective field theory for generic black holes in de Sitter spaces should be formulated within the region between the event horizon (EH) and the cosmological horizon (CH), to integrate out the classically irrelevant ingoing modes at the EH and the classically irrelevant outgoing modes at the CH, respectively.