We study two Schwarzschild black holes as the spherically symmetric solution to the zero mode effective action in the dilatonic domain wall model. This corresponds to the dilatonic version of the Randall-Sundrum(RS) model. Further this can be reduced to the Brans-Dicke(BD) model with the potential, which leads to the RS black hole. In the absence of the potential, one finds the known BD black h...

Black hole uniqueness is known to fail in higher dimensions, and the multiplicity of black hole phases leads to phase transitions physics in General Relativity. The black-hole black-string transition is a prime realization of such a system and its phase diagram has been the subject of considerable study in the last few years. The most surprising results seem to be the appearance of critical dim...

We derive an exact expression for the partition function of the Euclidean BTZ black hole. Using this, we show that for a black hole with large horizon area, the correction to the Bekenstein-Hawking entropy is −3/2 log(area), in agreement with that for the Schwarzschild black hole obtained in the four dimensional canonical gravity formalism and also in a Lorentzian computation of BTZ black hole ...

Recently, we derived an improved universal upper bound to the entropy of a charged system S ≤ π(2Eb − q 2)/¯ h. There was, however, some uncertainty in the value of the numerical factor which multiplies the q 2 term. In this paper we remove this uncertainty; we rederive this upper bound from an application of the generalized second law of thermodynamics to a gedanken experiment in which an entr...

We have performed 2.5-dimensional general relativistic magnetohydrodynamic (MHD) simulations of collapsars including a rotating black hole. This paper is an extension of our previous paper (Mizuno et al. 2004). The current calculation focuses on the effect of black hole rotation using general relativistic MHD with simplified microphysics, i.e., we ignore neutrino cooling, physical equation of s...

We study the energetics of a black hole-accretion disk system with magnetic connection: a Keplerian disk is connected to a Kerr black hole by a large-scale magnetic field going through the transition region. We assume that the magnetic field is locked to the inner boundary of the disk and corotates with the inner boundary, the accretion rate is low but the accretion from the disk can still prov...

I consider a toy model of self-regulated black hole accretion. The black hole grows through Bondi accretion and a fraction of the accretion power is distributed as thermal feedback into the surrounding gas. The gas expands or contracts until AGN heating and radiative cooling balance each other. The balance of heating and cooling is used to determine a quasi-equilibrium temperature at which the ...

The third law of black hole thermodynamics is violated in the test fluid approximation for the process of phantom energy accretion onto a rotating or an electrically charge black hole. The black hole mass is continuously decreasing but the angular momentum or electric charge is remaining constant in this process. As a result, a black hole reaches the extreme state during a finite time with a th...

The Fundamental Plane for black hole activity constitutes a tight correlation between jet power, X-ray luminosity, and black hole mass. Under the assumption that a Blandford–Znajek-type mechanism, which relies on black hole spin, contributes non-negligibly to jet production, the sufficiently small scatter in the Fundamental Plane shows that black hole spin differences of | a| ∼ 1 are not typica...