Black holes in the classical and quantum world

Advances in High Energy Physics, 2019

2019

El objetivo de la presente tesis es profundizar en diversos aspectos de la fisica de los agujeros negros. Tanto en lo que respecta a sus caracteristicas constitutivas fundamentales, su "estructura" interna, como a la posibilidad de observar o detectar mediante observaciones astrofisicas ciertos efectos producto de su dinamica.Por un lado, hemos seguido las ideas de Dvali, Gomez et al. quienes han sugerido la posibilidad de que un agujero negro sea un condensado de Bose—Einstein de gravitones debilmente interactuantes. En nuestro caso hemos estudiado la existencia de este tipo de soluciones sobre diferentes metricas de agujero negro (Schwarzschild y Reissner— Nordstrom) que actuarian como potencial confinante para dichos condensados. Un parametro necesario para ello, es el equivalente a un potencial quimico que debe ser incorporado a la relatividad general. Cabe destacar que la solucion encontrada puede ser interpretada como la funcion de campo medio del condensado. Ademas ...

Arxiv preprint arXiv:0711.2279, 2007

The possible existence of black holes has fascinated scientists at least since Michell and Laplace's proposal that a gravitating object could exist from which light could not escape. In the 20th century, in light of the general theory of relativity, it became apparent that, were such objects to exist, their structure would be far richer than originally imagined. Today, astronomical observations strongly suggest that either black holes, or objects with similar properties, not only exist but may well be abundant in our universe. In light of this, black hole research is now not only motivated by the fascinating theoretical properties such objects must possess but also as an attempt to better understand the universe around us. We review here some selected developments in black hole research, from a review of its early history to current topics in black hole physics research. Black holes have been studied at all levels; classically, semi-classically, and more recently, as an arena to test predictions of candidate theories of quantum gravity. We will review here progress and current research at all these levels as well as discuss some proposed alternatives to black holes.

Journal of Emerging Technologies and Innovative Research (JETIR), 2018

Black holes are often defined as areas from which nothing, not even light, can escape. There is good reason to believe, however, that particles can get out of them by "tunneling" The popular conception of black holes reflects the behavior of the massive black holes found by astronomers and described by classical general relativity. These objects swallow up whatever comes near and emit nothing. Physicists who have tried to understand the behavior of black holes from a quantum mechanical point of view, however, have arrived at quite a different picture. The difference is analogous to the difference between thermodynamics and statistical mechanics. The thermodynamic description is a good approximation for a macroscopic system, but statistical mechanics describes what one will see if one looks more closely. After a brief review of quantum black hole physics, it is shown how the dynamical properties of a quantum black hole may be deduced to a large extent from Standard Model Physics, extended to scales near the Planck length, and combined with results from perturbative quantum gravity. Together, these interactions generate a Hilbert space of states on the black hole horizon, which can be investigated, displaying interesting systematics by themselves. To make such approaches more powerful, a study is made of the black hole complementarity principle, from which one may deduce the existence of a hidden form of local conformal invariance. Finally, the question is raised whether the principles underlying Quantum Mechanics are to be sharpened in this domain of physics as well. There are intriguing possibilities.

Journal of High Energy Physics, Gravitation and Cosmology, 2019

The black hole is a region in space where things may fall into it but nothing can come out. We present a study of the physics of a black hole using a quantum field theory frame based on the WZW model in a suitable mathematical frame. Based on the Schwarzschild metric, we show the different regions of our universe with the present singularities. Then we introduce the calculation of a black hole mass using the perturbation theory. We further discuss Hawking radiation and its quantum mechanical implications. At some limits, the space time can represent a black hole with a singularity hidden by the horizon.

1998

In this paper, starting from vortices we are finally lead to a treatment of Fermions as Kerr-Newman type Black Holes wherein we identify the horizon at the particle's Compton wavelength periphery. A naked singularity is avoided and the singular processes inside the horizon of the Black Hole are identified with Quantum Mechanical effects within the Compton wavelength. Inertial mass, gravitation,

International Journal of Modern Physics A, 2002

We describe some specific quantum black hole model. It is pointed out that the origin of a black hole entropy is the very process of quantum gravitational collapse. The quantum black hole mass spectrum is extracted from the mass spectrum of the gravitating source. The classical analog of quantum black hole is constructed.

Eprint Arxiv 0805 2082, 2008

Black holes are perhaps the most strange and fascinating objects known to exist in the universe. Our understanding of space and time is pushed to its limits by the extreme conditions found in these objects. They can be used as natural laboratories to test the behavior of matter in very strong gravitational fields. Black holes seem to play a key role in the universe, powering a wide variety of phenomena, from X-ray binaries to active galactic nuclei. In this article we will review the basics of black hole physics.

Physics Letters B, 1990

A quantum mechanical model ofa Schwar-zschild black hole is constructed. This model is based on the simplest classical model, namely, a spherical thin dust shell as a source for a black hole mass. Such a mechanical system has only one degree of freedom which is quantized. The Klein-Gordon-type equation obtained exhibits some interesting fcaturcs. This equation is an equation in finite differences and not a differential equation. There are nonlocalitics near the singularities (r=0) and at the horizon. For the large black holes this equation can be approximated by an ordinary differential equation, which has one solution in the interior regions of a black hole. This is an ingoing wave in the collapse region and an outgoing wave in the anticollapse regions. An approximate expression for the bound states is obtained.

In this paper we propose a full revised version of a simple model, which allows a formal derivation of an infinite set of Schwarzschild-Like solutions (non-rotating and non-charged "black holes"), without resorting to General Relativity. A new meaning is assigned to the usual Schwarzschild-Like solutions (Hilbert, Droste, Brillouin, Schwarzschild), as well as to the very concepts of "black hole" and "event horizon". We hypothesize a closed Universe, homogeneous and isotropic, characterized by a further spatial dimension. Although the Universe is postulated as belonging to the so-called oscillatory class (in detail, we consider a simple-harmonically oscillating Universe), the metric variation of distances is not thought to be a real phenomenon (otherwise, we would not be able to derive any static solution): on this subject, the cosmological redshift is regarded as being caused by a variation over time of the Planck "constant". Time is considered as being absolute. The influence of matter/energy on space is analysed by the superposition of three three-dimensional scenarios. A short section is dedicated to the so-called gravitational redshift which, once having imposed the conservation of energy, may be ascribable to a local variability of the Planck "constant".