scholarly journals A Little Quantum Help for Cosmic Censorship and a Step Beyond All That

2013 ◽  
Vol 2013 ◽  
pp. 1-4
Author(s):  
Nikolaos Pappas
Keyword(s):  
General Relativity ◽  
Event Horizon ◽  
Crucial Role ◽  
Naked Singularity ◽  
Cosmic Censorship ◽  
Usual Sense ◽  
Naked Singularities ◽  
Open Question ◽  
Heisenberg's Uncertainty Principle ◽  
The Universe

The hypothesis of cosmic censorship (CCH) plays a crucial role in classical general relativity, namely, to ensure that naked singularities would never emerge, since it predicts that whenever a singularity is formed an event horizon would always develop around it as well, to prevent the former from interacting directly with the rest of the Universe. Should this not be so, naked singularities could eventually form, in which case phenomena beyond our understanding and ability to predict could occur, since at the vicinity of the singularity both predictability and determinism break down even at the classical (e.g., nonquantum) level. More than 40 years after it was proposed, the validity of the hypothesis remains an open question. We reconsider CCH in both its weak and strong versions, concerning point-like singularities, with respect to the provisions of Heisenberg’s uncertainty principle. We argue that the shielding of the singularities from observers at infinity by an event horizon is also quantum mechanically favored, but ultimately it seems more appropriate to accept that singularities never actually form in the usual sense; thus no naked singularity danger exists in the first place.

Cosmic Censorship!: Thermal Transport in a ‘Naked’ Black Hole

2011 ◽  
Vol 312-315 ◽  
pp. 27-32
Author(s):  
R. Leticia Corral Bustamante ◽  
Aarón Raúl Rodríguez-Corral ◽  
T.J Amador-Parra ◽  
E.A. Vázquez-Tapia
Keyword(s):  
Black Hole ◽  
Angular Momentum ◽  
Event Horizon ◽  
Naked Singularity ◽  
Major Axis ◽  
Cosmic Censorship ◽  
Einstein Equations ◽  
Semi Major Axis ◽  
High Entropy ◽  
Apparent Horizons

Cosmic censorship!: black hole wrapped up by its entropy and hidden by its event horizon. In this paper, we postulate a metric to solve the Einstein equations of general relativity, which predicts the thermodynamic behavior of a gigantic mass that collapses to a black hole; taking into account the third law of thermodynamics that states that neither physical process can produce a naked singularity. However, under certain conditions, the model allows to evident violation to the cosmic censorship, exposing the hole nakedness. During the collapse of the hole, quantum effects appear: the area decrease and radiation produced has a high entropy, so that increases total entropy and expose the presence of the hole, while the appearance of the event horizon hide the singularity of the exterior gazes. It is verified that in certain circumstances, the model predicts that the hole mass is bigger than its angular momentum; and in all circumstances, this predicts an hole with enormous superficial graveness that satisfy a relationship of the three parameters that describe the hole (mass, charge and angular momentum); factors all indicative that the singularity is not naked. Then, there are no apparent horizons in accord with cosmic censorship conjecture. Even though the surface gravity of the hole prevents destroying its horizon wrapping singularity, there exists evidence of this singularity by the results of the spin-mass relationship and the escape velocity obtained. The lost information and the slow rate of rotation of the semi-major axis of the mass (dragging space and time around itself as it rotates), agree with Einstein's prediction, show the transport of energy through heat and mass transfer, which were measured by entropy of the hole by means of coordinated semi-spherical that include the different types of intrinsic energy to the process of radiation of the hole event horizon.

IS THE NAKED SINGULARITY INCOMPATIBLE TO QUANTUM GRAVITY?

2005 ◽  
Vol 20 (24) ◽  
pp. 1823-1829 ◽  
Author(s):  
LI XIANG ◽  
YOU-GEN SHEN
Keyword(s):  
Generalized Uncertainty Principle ◽  
Charged Particles ◽  
Naked Singularity ◽  
Cosmic Censorship ◽  
Second Law ◽  
De Sitter Spacetime ◽  
De Sitter ◽  
Naked Singularities ◽  
Sitter Spacetime ◽  
Cosmic Censorship Hypothesis

In this paper two consequences of the generalized uncertainty principle (GUP) are discussed in a heuristic manner. Both could be regarded as the evidences that prefer the cosmic censorship hypothesis (CCH). The first one is that the second law tends to decline the massless charged particles if the effects of the GUP on the thermodynamics of a de Sitter spacetime are considered. This weakens the threat to the horizon of an extreme charged black hole. The second one is that the uv/ir correspondence provides a constraint on the relation between the energy and the size of a system, which is incompatible to the naked singularities.

Extremal Kerr Black Holes, Naked Singularity & Wormholes

2020 ◽  
Author(s):  
Deep Bhattacharjee
Keyword(s):  
Black Holes ◽  
General Relativity ◽  
Black Hole ◽  
Angular Momentum ◽  
Event Horizon ◽  
Kerr Black Hole ◽  
Naked Singularity ◽  
Kerr Metric ◽  
Spin Angular Momentum ◽  
The Way

This paper is totally based on the mathematical physics of the Black holes. In Einstein’s theory of “General Relativity”, Schwarzschild solution is the vacuum solutions of the Einstein Field Equations that describes the gravity potential from outside the body of a spherically symmetric object having zero charge, zero mass and zero cosmological constant[1]. It was discovered by Karl Schwarzschild in 1916, a little more than a month after the publication of the famous GR and the singularity is a point singularity which can be best described as a coordinate singularity rather than a real singularity, however, the drawback of this theory is that it fails to take into account the real life scenario of black holes with charge and spin angular momentum. The black hole is based on event horizon and Schwarzschild radius. However, Physicists were trying to develop a metric for the real life scenario of a black hole with a spin angular momen-tum and ultimately the exact solution of a charged rotating black hole had been discovered by Roy Kerr in 1965 as the Kerr-Newman metric[2][3]. The Kerr metric is one of the toughest metric in physics and is the extensional generalization to a rotating body of the Schwarzschild metric. The metric describes the vacuum geometry of space-time around a rotating axially-symmetric black hole with a quasipotential event horizon. In Kerr metric there are two event hori-zons (inner and outer), two ergospheres and an ergosurface. The most important effect of the Kerr metric is the frame dragging (also known as Lense-Thirring Precession) is a distinctive prediction of General relativity. The first direct observation of the collision of two Kerr Black Holes has been discovered by LIGO in 2016 hence setting up a milestone of General Relativity in the history of Physics. Here, the Kerr metric has been introduced in the Boyer-Lindquist forms and it is derived from the Schwarzschild metric using the Spin-Coefficient formalism. According to the “Cosmic Censorship Hypothesis”, a naked singularity cannot exist in nature as nature always hides the singularity via an event horizon. However, in this paper I will prove the existence of the “Naked Singularity" taking the advantage of the Ring Singularity of the Kerr Black Hole and thereby making the way to manipulate the mathematics by taking the larger root of Δ as zero and thereby vanishing the ergosphere and event horizon making the way for the naked ring singularity which can be easily connected via a cylindrical wormhole and as ‘a wormhole is a black hole without an event horizon’ therefore, this cylindrical connection paved the way for the Einstein-Rosen Bridge allowing particles or null rays to travel from one universe to another ending up in a future directed Cauchy horizon while changing constantly from spatial to temporal and again spatial paving the entrance to another Kerr Black hole (which would act as a white hole) in the other universes. I will not go in detail about the contradiction of ‘Chronology Protection Conjecture” [4]whether the Stress-Energy-Momentum Tensor can violate the ANEC (Average Null Energy Conditions) or not with the values of less than zero or greater than, equal to zero, instead I will focus definitely on the creation of the mathematical formulation of a wormhole from a Naked Ring Kerr Singularity of a Kerr Black Hole without any event horizon or ergosphere. Another important thing to mention in this paper is that I have taken the time to be imaginary[5] as because, a singularity being an eternal point of time can only be smoothen out if the time is imaginary rather than real which will allow the particle or null rays inside a wormhole to cross the singularity and making entrance to the other universe. The final conclusion would be to determine the mass-energy equivalence principle as spin angular momentum increases with a decrease in BH mass due to the vanishing event horizon and ergosphere thereby maintaining the equivalence via apparent and absolute masses in relation to spin J along the orthogonal Z axis. A ‘NAKED SINGULARITY’ alters every parameters of a BH and to include this parameters along with affine spin coefficient, it has been proved that without any spin angular momentum the generation of wormhole and vanishing of event horizon and singularity is not possible.

scholarly journals Testing Cosmic Censorship in Kerr-Like Collapse Situations

1997 ◽  
Vol 12 (30) ◽  
pp. 2237-2242
Author(s):  
Wiesław Rudnicki
Keyword(s):  
Gravitational Collapse ◽  
Naked Singularity ◽  
Cosmic Censorship ◽  
Kerr Solution ◽  
Initial State ◽  
Final State ◽  
Open Problems ◽  
Naked Singularities ◽  
Cosmic Censorship Hypothesis

According to the cosmic censorship hypothesis of Penrose, naked singularities should never occur in realistic collapse situations. One of the major open problems in this context is the existence of a naked singularity in the Kerr solution with |a|>m; this singularity can be interpreted as the final product of collapse of a rapidly rotating object. Assuming that certain very general and physically reasonable conditions hold, we show here, using the global techniques, that a realistic gravitational collapse of any rotating object, which develops from a regular initial state, cannot lead to the formation of a final state resembling the Kerr solution with a naked singularity. This result supports the validity of the cosmic censorship hypothesis.

scholarly journals MASS QUADRUPOLE AS A SOURCE OF NAKED SINGULARITIES

2011 ◽  
Vol 20 (10) ◽  
pp. 1779-1787 ◽  
Author(s):  
HERNANDO QUEVEDO
Keyword(s):  
Gravitational Field ◽  
Quadrupole Moment ◽  
Event Horizon ◽  
Naked Singularity ◽  
Empty Space ◽  
Effective Field ◽  
Naked Singularities ◽  
Test Particles ◽  
Repulsive Gravity ◽  
Mass Quadrupole

We investigate the gravitational field of a static mass with quadrupole moment in empty space. It is shown that in general this configuration is characterized by the presence of curvature singularities without a surrounding event horizon. These naked singularities generate an effective field of repulsive gravity which, in turn, drastically changes the behavior of test particles. As a possible consequence, the accretion disk around a naked singularity presents a particular discontinuous structure.

scholarly journals INSTABILITIES OF NAKED SINGULARITIES AND BLACK HOLE INTERIORS IN GENERAL RELATIVITY

2009 ◽  
Vol 24 (08n09) ◽  
pp. 1578-1582 ◽  
Author(s):  
GUSTAVO DOTTI ◽  
REINALDO J. GLEISER ◽  
JORGE PULLIN ◽  
IGNACIO F. RANEA-SANDOVAL ◽  
HÉCTOR VUCETICH
Keyword(s):  
Black Holes ◽  
General Relativity ◽  
Black Hole ◽  
Recent Work ◽  
Kerr Black Hole ◽  
Cosmic Censorship ◽  
Negative Mass ◽  
Naked Singularities ◽  
Gravitational Perturbations ◽  
Inner Horizon

Metrics representing black holes in General Relativity may exhibit naked singularities for certain values of their parameters. This is the case for super-extremal (J2 > M > 0) Kerr and super-extremal (|Q| > M > 0) Reissner-Nördstrom spacetimes, and also for the negative mass Schwarzschild spacetime. We review our recent work where we show that these nakedly singular spacetimes are unstable under linear gravitational perturbations, a result that supports the cosmic censorship conjecture, and also that the inner stationary region beyond the inner horizon of a Kerr black hole (J2 < M) is linearly unstable.

scholarly journals THE UNIVERSE OF FLUCTUATIONS

1998 ◽  
Vol 13 (15) ◽  
pp. 2599-2612 ◽  
Author(s):  
B. G. SIDHARTH
Keyword(s):  
General Relativity ◽  
Black Hole ◽  
Gravitational Interaction ◽  
Structure Constant ◽  
Quantum Statistical Mechanics ◽  
Naked Singularity ◽  
Effective Field ◽  
Fine Structure Constant ◽  
Age Of The Universe ◽  
The Universe

We discuss the recent model of a Quantum Mechanical Black Hole (QMBH) which describes the most fundamental known particles, the leptons and approximately the quarks in terms of the Kerr–Newman Black Hole with a naked singularity shielded by Zitterbewegung effects. This goes beyond the Zitterbewegung and self interaction models of Barut and Bracken, Hestenes, Chacko and others and provides a unified picture which amongst other things gives a rationale for and an insight into: (1) The apparently inexplicable reason why complex space–time transformations lead to the Kerr–Newman metric in General Relativity. (2) The value of the fine structure constant. (3) The ratio between electromagnetic and gravitational interaction strengths. (4) The anomalous gyromagnetic ratio for the electron. (5) Why the neutrino is left-handed. (6) Why the charge is discrete. In the spirit of Effective Field Theories, this model provides an alternative formalism for Quantum Theory and also for its combination with General Relativity. Finally a mechanism for the formation of these QMBH or particles is explored within the framework of Stochastic Electrodynamics, QED and Quantum Statistical Mechanics. The cosmological implications are then examined. It turns out that a surprisingly large number of facts, including some which were hitherto inexplicable. follow as a consequence of the model. These include a theoretical deduction of the Mass, Radius and Age of the Universe, also the values of Hubble's constant and the Cosmological constant.

scholarly journals Predictivity lost, predictivity regained: A Miltonian cosmic censorship conjecture

2020 ◽  
Vol 29 (14) ◽  
pp. 2043021
Author(s):  
Roberto Emparan
Keyword(s):  
Black Holes ◽  
General Relativity ◽  
Predictive Power ◽  
Planck Scale ◽  
Cosmic Censorship ◽  
Naked Singularities ◽  
Zero Mass ◽  
Opening Up ◽  
Cosmic Censorship Conjecture ◽  
Planck Scale Physics

Cosmic censorship is known to fail in some well-controlled phenomena, calling into question the predictive power of General Relativity and opening up the possibility of observing Planck-scale physics. We propose that the cosmic censorship conjecture can be amended so that its spirit prevails. Naked singularities that, classically, have zero mass are allowed. Physically, these are Planck-sized “black holes”, which evaporate in a few Planck times. General Relativity fails only for a tiny interval in time, to then quickly regain control in a Miltonian evolution that returns us to the predictive paradise of Einstein’s equations. If this refinement of the conjecture is correct, then, even though Nature does allow to expose breakdowns in the smooth fabric of spacetime, it limits them to a mostly harmless minimum.

scholarly journals Vaidya Collapse with Nonzero Radial Pressure and Charge

Axioms ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 52
Author(s):  
Aroonkumar Beesham
Keyword(s):  
Black Holes ◽  
General Relativity ◽  
Initial Conditions ◽  
Radial Pressure ◽  
Cosmic Censorship ◽  
Cosmological Parameter ◽  
Naked Singularities ◽  
Physical Conditions ◽  
Cosmic Censorship Hypothesis ◽  
Nonzero Charge

The cosmic censorship hypothesis is regarded as one of the most important unsolved problems in classical general relativity; viz., will generic gravitational collapse of a star after it has exhausted its nuclear fuel lead to black holes only, under reasonable physical conditions. We discuss the collapse of a fluid with nonzero radial pressure within the context of the Vaidya spacetime considering a decaying cosmological parameter as well as nonzero charge. Previously, a similar analysis was done, but without considering charge. A decaying cosmological parameter may also be associated with dark energy. We found that both black holes and naked singularities can form, depending upon the initial conditions. Hence, charge does not restore the validity of the hypothesis. This provides another example of the violation of the cosmic censorship hypothesis. We also discuss some radiating rotating solutions, arriving at the same conclusion.

GRAVITY CAN BE OBSERVED IN THE ABSENCE OF CURVED SPACETIME, THUS CURVED SPACETIME IS NOT RESPONCIBLE FOR GRAVITY

2015 ◽  
Vol 8 (1) ◽  
pp. 1976-1981
Author(s):  
Casey McMahon
Keyword(s):  
General Relativity ◽  
Special Relativity ◽  
Relative Position ◽  
Gravitational Force ◽  
Curved Spacetime ◽  
Relative Time ◽  
Curved Space ◽  
Spacetime Curvature ◽  
Equivalence Model ◽  
The Universe

The principle postulate of general relativity appears to be that curved space or curved spacetime is gravitational, in that mass curves the spacetime around it, and that this curved spacetime acts on mass in a manner we call gravity. Here, I use the theory of special relativity to show that curved spacetime can be non-gravitational, by showing that curve-linear space or curved spacetime can be observed without exerting a gravitational force on mass to induce motion- as well as showing gravity can be observed without spacetime curvature. This is done using the principles of special relativity in accordance with Einstein to satisfy the reader, using a gravitational equivalence model. Curved spacetime may appear to affect the apparent relative position and dimensions of a mass, as well as the relative time experienced by a mass, but it does not exert gravitational force (gravity) on mass. Thus, this paper explains why there appears to be more gravity in the universe than mass to account for it, because gravity is not the resultant of the curvature of spacetime on mass, thus the “dark matter” and “dark energy” we are looking for to explain this excess gravity doesn’t exist.

Sign in / Sign up

Export Citation Format

Share Document