相关论文: Reflection on event horizon for collapsing black h…

We elucidate how black holes form in trans-Planckian collisions. In the rest frame of one of the incident particles, the gravitational field of the other, which is rapidly moving, looks like a gravitational shock wave. The shock wave…

We consider the space-time associated with the evaporation of a black hole by quantum mechanical tunnelling events. It is shown that the surface through which tunnelling occurs is distinct from the global event horizon, and that this has…

When a massive test particle or a photon fall radially into a black hole, their energy, as measured by a static observer located very close to the horizon, diverges. In introductory courses on General Relativity, this fact gives rise to…

The work on black holes immersed in external fields is reviewed in both test-field approximation and within exact solutions. In particular we pay attention to the effect of the expulsion of the flux of external fields across charged and…

There is persistent and endemic confusion between the true (future) horizon and the illusory (past) horizon of a black hole. The illusory horizon is the redshifting surface of matter that fell into the black hole long ago. A person who…

Black holes harbor a spacetime singularity of infinite curvature, where classical spacetime physics breaks down, and current theory cannot predict what will happen. However, the singularity is invisible from the outside because strong…

Event horizons are (generically) not physically observable. In contrast, apparent horizons (and the closely related trapping horizons) are generically physically observable --- in the sense that they can be detected by observers working in…

Quantum gravity phenomenology suggests the interesting possibility that black holes are not eternal. Collapse could be halted by some unknown mechanism, or Hawking radiation might leave behind a regular spacetime. Here we investigate a…

I review elements of the foundations of black-hole theory with attention to problematic issues, and describe some techniques which either seem to help with the difficulties or at least investigate their scope. The definition of black holes…

A simple classical consideration of black hole formation and evaporation times focusing solely on the frame of an observer at infinity demonstrates that an infall cutoff outside the event horizon of a black hole must be imposed in order for…

We discuss whether black holes could persist in a universe which recollapses and then bounces into a new expansion phase. Whether the bounce is of classical or quantum gravitational origin, such cosmological models are of great current…

Black holes are among the most intriguing objects in modern physics. Their influence ranges from powering quasars and other active galactic nuclei, to providing key insights into quantum gravity. We review the observational evidence for…

In the last four decades different programs have been carried out aiming at understanding the final fate of gravitational collapse of massive bodies once some prescriptions for the behaviour of gravity in the strong field regime are…

It was recently shown that black holes could be bouncing stars as a consequence of quantum gravity. We investigate the astrophysical signals implied by this hypothesis, focusing on primordial black holes. We consider different possible…

Recent developments have ushered in a new era in the field of black hole astrophysics, providing our first direct view of the remarkable environment near black hole event horizons. These observations have enabled astronomers to confirm…

From the microscopic point of view, realistic black holes are time-dependent and the teleological concept of event horizon fails. At present, the apparent or the trapping horizon seem its best replacements in various areas of black hole…

Black holes pose a serious problem in the cyclic or oscillating cosmology. It is speculated that, in the cyclic universe with phantom turnarounds, black holes will be torn apart by the phantom energy before turnaround before they can create…

It has been taken as a truth that collapsing matter can eventually cross the horizon and enter into the interior of a black hole in a finite proper time. However, the Rindler/tachyon dual description we suggest recently implies that this…

Because of the very definition of black holes --- no light escapes them and falling objects get infinitely faint when approaching --- it is impossible to ever prove that they exist. However, electromagnetic and gravitational-wave…

Quantum-gravity effects in black holes are generally expected to be unobservable if they set in at transplanckian curvature scales. Here, we challenge this expectation. A near-critical spin parameter can serve as a lever arm that translates…