Almheiri et al. have emphasized that otherwise reasonable beliefs about black hole evaporation are incompatible with the monogamy of quantum entanglement, a general property of quantum mechanics. We investigate the final-state projection model of black hole evaporation proposed by Horowitz and Maldacena, pointing out that this model admits cloning of quantum states and polygamous entanglement, ...

The accurate prediction of wellbore temperature distribution helps to accurately estimate well pressure profile and bottom-hole pressure (BHP) which is important in the under-balanced drilling (UBD) operation. In this paper effect of temperature variation due to heat transfer of drilling fluid with the formation and also oil and gas production from the reservoir into the annulus in under-balanc...

Considering the small warping parabolic heavy hole model with the quasi-elastic approximation in acoustic phonon scattering, it is shown that the hole scattering length is independent of the hole energy. This result now makes it possible to solve the Boltzmann transport equation to obtain a simple analytical solution for the ballistic hole transport in a thin and uniformly doped base of a pnp t...

We derive and discuss black–hole solutions to the gravitating O(3) σ model in (2+1) dimensions. Three different kinds of static black holes are found. One of these resembles the static BTZ black hole, another is completely free of singularities, and the last type has the same Penrose diagram as the (3+1)–dimensional Schwarzschild black hole. We also construct static and dynamical multi–black ho...

We consider the behavior of the innermost stable circular orbit (ISCO) in the magnetic field near “dirty” (surrounded by matter) axially symmetric black holes. The cases of near-extremal, extremal, and nonextremal black holes are analyzed. For nonrotating black holes, in the strong magnetic field ISCO approaches the horizon (when backreaction of the field on the geometry is neglected). Rotation...

Small black holes should have formed in the early Universe if the density contrast was high enough. This article aims at giving a biased and partial short overview of the latest breakthroughs in this field. It first deals with tentative experimental detections thanks to gamma-rays and cosmic-rays. Primordial black holes (PBHs) are then considered as probes of the very small cosmological scales,...

We present a matrix model which is intended as a toy model of the gauge dual of an AdS black hole. In particular, it captures the key property that at infiniteN correlators decay to zero on long time scales, while at finite N this cannot happen. The model consists of a harmonic oscillator in the adjoint which acts as a heat bath for a particle in the fundamental representation. The Schwinger-Dy...

The statistical mechanics of black holes arbitrarily far from extremality is modeled by a gas of weakly interacting strings. As an effective low energy description of black holes the model provides a number of highly non-trivial consistency checks and predictions. Speculations on a fundamental origin of the model suggest surprising simplifications in non-perturbative string theory, even in the ...

We investigate dynamical instability of a two-dimensional quantum black hole model considered by Lowe in his study of Hawking evaporation. The model is supposed to express a black hole in equilibrium with a bath of Hawking radiation. It turns out that the model has at least one instability modes for a wide range of parameters, and thus it is unstable.