Lower-dimensional corpuscular gravity and the end of black hole evaporation

2019 ◽  
Vol 34 (22) ◽  
pp. 1950174
Author(s):  
Roberto Casadio ◽  
Andrea Giusti ◽  
Jonas Mureika
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Occupation Number ◽  
Planck Scale ◽  
Friedmann Equation ◽  
Dimensional Spacetime ◽  
Spatial Dimensions ◽  
Bose Einstein ◽  
Lower Dimensional ◽  
Hawking Evaporation

Black holes in [Formula: see text] spatial dimensions are studied from the perspective of the corpuscular model of gravitation, in which black holes are described as Bose–Einstein condensates (BEC) of (virtual soft) gravitons. In particular, since the energy of these gravitons should increase as the black hole evaporates, eventually approaching the Planck scale, the lower-dimensional cases could provide important insight into the late stages and end of Hawking evaporation. We show that the occupation number of gravitons in the condensate scales holographically in all dimensions as [Formula: see text], where [Formula: see text] is the relevant length for the system in the [Formula: see text]-dimensional spacetime. In particular, this analysis shows that black holes cannot contain more than a few gravitons in [Formula: see text]. Since dimensional reduction is a common feature of many models of quantum gravity, this result can shed light on the end of the Hawking evaporation. We also consider [Formula: see text]-dimensional cosmology in the context of corpuscular gravity and show that the Friedmann equation reproduces the expected holographic scaling as in higher dimensions.

Frontiers of Quantum Black Holes

2020 ◽  
Vol 29 (11) ◽  
pp. 10-16
Author(s):  
Wontae KIM ◽  
Mu-In PARK
Keyword(s):  
Black Holes ◽  
General Relativity ◽  
Black Hole ◽  
Direct Detection ◽  
Occupation Number ◽  
Theory Of Relativity ◽  
General Theory Of Relativity ◽  
Quantum Radiation ◽  
Points Of View ◽  
Massless Quantum

A black hole is a theoretical prediction of Einstein’s general theory of relativity, differently from Newtonian gravity, which is a non-relativistic gravity. In recent few years, its direct detection via gravitational waves and other multi-messenger observations have made it possible to test the prediction and hence its associated general relativity. From purely theoretical points of view, general relativity cannot be a complete description due to its not being compatible with quantum mechanics, which is a successful description of microscopic objects. In this article, we introduce the conceptional development of quantum-gravity theories and give brief sketches of fundamental problems in quantum black holes. As an interesting model of quantum black holes, we consider a collapsing shell of matter to form a Hayward black hole and investigate semiclassically quantum radiation from the shell. By using the Israel’s formulation and the functional Schrödinger formulation for massless quantum radiation, we find that the Hawking temperature can be deduced from the occupation number of excited states when the shell approaches its own horizon.

scholarly journals Ten shades of black

2015 ◽  
Vol 24 (12) ◽  
pp. 1544007 ◽  
Author(s):  
Shahar Hod
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Radiation Spectrum ◽  
Black Hole Physics ◽  
Black Body ◽  
Black Hole Radiation ◽  
Dimensional Spacetime ◽  
Opposite Behavior ◽  
Curvature Potential ◽  
Energy Dependent

The holographic principle has taught us that, as far as their entropy content is concerned, black holes in (3 + 1)-dimensional curved spacetimes behave as ordinary thermodynamic systems in flat (2 + 1)-dimensional spacetimes. In this paper, we point out that the opposite behavior can also be observed in black-hole physics. To show this we study the quantum Hawking evaporation of near-extremal Reissner–Nordström (RN) black holes. We first point out that the black-hole radiation spectrum departs from the familiar radiation spectrum of genuine (3 + 1)-dimensional perfect black-body emitters. In particular, the would be black-body thermal spectrum is distorted by the curvature potential which surrounds the black-hole and effectively blocks the emission of low-energy quanta. Taking into account the energy-dependent gray-body factors which quantify the imprint of passage of the emitted radiation quanta through the black-hole curvature potential, we reveal that the (3 + 1)-dimensional black holes effectively behave as perfect black-body emitters in a flat (9 + 1)-dimensional spacetime.

Three-dimensional static black hole with Λ and nonlinear electromagnetic fields and its thermodynamics

2019 ◽  
Vol 28 (12) ◽  
pp. 1950160
Author(s):  
M. B. Tataryn ◽  
M. M. Stetsko
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Electromagnetic Fields ◽  
Three Dimensional ◽  
Nonlinear Electrodynamics ◽  
Extended Phase Space ◽  
Field Equations ◽  
Extended Phase ◽  
Dimensional Spacetime ◽  
Static Black Hole

Static black hole with the Power Maxwell invariant (PMI), Born–Infeld (BI), logarithmic (LN), exponential (EN) electromagnetic fields in three-dimensional spacetime with cosmological constant was studied. It was shown that the LN and EN fields represent the Born–Infeld type of nonlinear electrodynamics. It the framework of General Relativity the exact solutions of the field equations were obtained, corresponding thermodynamic functions were calculated and the [Formula: see text] criticality of the black holes in the extended phase-space thermodynamics was investigated.

scholarly journals Black Holes and Wormholes in Extended Gravity

Universe ◽  
2020 ◽  
Vol 6 (2) ◽  
pp. 25 ◽  
Author(s):  
Stanislav Alexeyev ◽  
Maxim Sendyuk
Keyword(s):  
Black Holes ◽  
General Relativity ◽  
Black Hole ◽  
Quantum Theory ◽  
Gravity Models ◽  
Astrophysical Data ◽  
Effective Gravity ◽  
Extended Gravity ◽  
Theory Of Gravity ◽  
Hawking Evaporation

We discuss black hole type solutions and wormhole type ones in the effective gravity models. Such models appear during the attempts to construct the quantum theory of gravity. The mentioned solutions, being, mostly, the perturbative generalisations of well-known ones in general relativity, carry out additional set of parameters and, therefore could help, for example, in the studying of the last stages of Hawking evaporation, in extracting the possibilities for the experimental or observational search and in helping to constrain by astrophysical data.

scholarly journals From the Schwarzschild Anti-de Sitter Black Hole to the Conformal Field Theory

2015 ◽  
Vol 2015 ◽  
pp. 1-7
Author(s):  
Akram Sadat Sefiedgar
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Central Charge ◽  
High Energy ◽  
De Sitter ◽  
Conformal Field ◽  
Verlinde Formula ◽  
Dimensional Spacetime ◽  
Very High Energy ◽  
High Energy Regime

The emergence of the quantum gravitational effects in a very high energy regime necessitates some corrections to the thermodynamics of black holes. In this letter, we investigate a possible modification to the thermodynamics of Schwarzschild anti-de Sitter (SAdS) black holes due to rainbow gravity model. Using the correspondence between a (d+1)-dimensional SAdS black hole and a conformal filed theory ind-dimensional spacetime, one may find the corrections to the Cardy-Verlinde formula from the modified thermodynamics of the black hole. Furthermore, we show that the corrected Cardy-Verlinde formula can also be derived by redefining the Virasoro operator and the central charge.

scholarly journals THERMODYNAMICS IN BLACK-HOLE/CFT CORRESPONDENCE

2013 ◽  
Vol 22 (12) ◽  
pp. 1342012 ◽  
Author(s):  
BIN CHEN ◽  
JIA-JU ZHANG
Keyword(s):  
Field Theory ◽  
Black Holes ◽  
Black Hole ◽  
Two Dimensional ◽  
Charged Black Holes ◽  
Conformal Field ◽  
Inner Horizon ◽  
Holographic Description ◽  
Area Law ◽  
Lower Dimensional

The area law of Bekenstein–Hawking entropy of the black hole suggests that the black hole should have a lower-dimensional holographic description. It has been found recently that a large class of rotating and charged black holes could be holographically described a two-dimensional (2D) conformal field theory (CFT). We show that the universal information of the dual CFT, including the central charges and the temperatures, is fully encoded in the thermodynamics laws of both outer and inner horizons. These laws, characterizing how the black hole responds under the perturbation, allows us to read different dual pictures with respect to different kinds of perturbations. The remarkable effectiveness of this thermodynamics method suggest that the inner horizon could play a key role in the study of holographic description of the black hole.

scholarly journals Cosmic cloaking of rich extra dimensions

2021 ◽  
Author(s):  
Aghil Alaee ◽  
Marcus Khuri ◽  
Hari Kunduri
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Extra Dimensions ◽  
Large Extra Dimensions ◽  
Dimensional Theory ◽  
Hoop Conjecture ◽  
Significant Size ◽  
The Universe ◽  
Lower Dimensional ◽  
Kaluza Klein

We present arguments that show why it is difficult to see rich extra dimensions in the universe. Conditions are found where significant size and variation of the extra dimensions in a Kaluza–Klein compactification lead to a black hole in the lower-dimensional theory. The idea is based on the hoop conjecture concerning black hole existence, as well as on the observation that dimensional reduction on macroscopically large, twisted, or highly dynamical extra dimensions contributes positively to the energy density in the lower-dimensional theory and can induce gravitational collapse. A threshold for the size is postulated on the order of [Formula: see text][Formula: see text]m, whereby extra dimensions of length above this level must lie inside black holes, thus cloaking them from the view of outside observers. The threshold depends on the size of the universe, leading to speculation that in the early stages of evolution truly macroscopic and large extra dimensions would have been visible.

Phase transition in decaying black holes

2020 ◽  
Vol 35 (31) ◽  
pp. 2050258
Author(s):  
Aloke Kumar Sinha
Keyword(s):  
Phase Transition ◽  
Black Holes ◽  
Black Hole ◽  
Phase Transitions ◽  
Quantum Black Hole ◽  
Dimensional Spacetime ◽  
The Stability ◽  
Derivatives Of ◽  
Physical Quantities ◽  
Thermal Stability Of

We had earlier derived the most general criteria for thermal stability of a quantum black hole, with arbitrary number of parameters, in any dimensional spacetime. These conditions appeared in form of a series of inequalities connecting second order derivatives of black hole mass with respect to its parameters. Some black holes like asymptotically flat rotating charged black holes do not satisfy all the stability criteria simultaneously, but do satisfy some of them in certain region of parameter space. They are known as “Quasi Stable” black holes. In this paper, we will show that quasi stable black holes although ultimately decay under Hawking radiation undergo phase transitions. These phase transitions are different from phase transition in ADS Schwarzschild black hole. These are marked by sign changes in certain physical quantities apart from specific heat of the black hole. We will also discuss the changes in the nature of fluctuations of the parameters of these quasi stable black holes with different phases.

scholarly journals Back-Reaction in Canonical Analogue Black Holes

2020 ◽  
Vol 10 (24) ◽  
pp. 8868
Author(s):  
Stefano Liberati ◽  
Giovanni Tricella ◽  
Andrea Trombettoni
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Density Distribution ◽  
Hawking Radiation ◽  
Einstein Condensate ◽  
Back Reaction ◽  
Unitary Evolution ◽  
Black Hole Evaporation ◽  
Bose Einstein Condensate ◽  
Bose Einstein

We study the back-reaction associated with Hawking evaporation of an acoustic canonical analogue black hole in a Bose–Einstein condensate. We show that the emission of Hawking radiation induces a local back-reaction on the condensate, perturbing it in the near-horizon region, and a global back-reaction in the density distribution of the atoms. We discuss how these results produce useful insights into the process of black hole evaporation and its compatibility with a unitary evolution.

ACCRETION MECHANISMS ONTO PRIMORDIAL BLACK HOLES

2010 ◽  
Vol 19 (08n10) ◽  
pp. 1249-1252
Author(s):  
D. C. GUARIENTO ◽  
J. E. HORVATH
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Dark Energy ◽  
Perfect Fluid ◽  
Test Fluid ◽  
Primordial Black Hole ◽  
Primordial Black Holes ◽  
Accretion Model ◽  
Hawking Evaporation

We study the evolution of a primordial black hole (PBH) taking into account the presence of dark energy modeled by a general perfect fluid. In the specific case of a stationary non-self-gravitating test fluid, the competition between radiation accretion, Hawking evaporation and the accretion of such a fluid has been studied in detail. The evaporation of PBHs is quite modified at late times by these effects. We address further generalizations of this scenario to consider other types of fluids, and point out early developments of a nonstationary accretion model.

Sign in / Sign up

Export Citation Format

Share Document