scholarly journals WHAT DID WE LEARN FROM STUDYING ACOUSTIC BLACK HOLES?

2002 ◽  
Vol 17 (20) ◽  
pp. 2721-2725 ◽  
Author(s):  
RENAUD PARENTANI
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Hawking Radiation ◽  
Asymptotic Properties ◽  
Planck Scale ◽  
Density Fluctuations ◽  
Effective Theory ◽  
Linear Dispersion ◽  
Black Hole Evaporation ◽  
Acoustic Black Holes

The study of acoustic black holes has been undertaken to provide new insights about the role of high frequencies in black hole evaporation. Because of the infinite gravitational redshift from the event horizon, Hawking quanta emerge from configurations which possessed ultra high (trans-Planckian) frequencies. Therefore Hawking radiation cannot be derived within the framework of a low energy effective theory; and in all derivations there are some assumptions concerning Planck scale physics. The analogy with condensed matter physics was thus introduced to see if the asymptotic properties of the Hawking phonons emitted by an acoustic black hole, namely stationarity and thermality, are sensitive to the high frequency physics which stems from the granular character of matter and which is governed by a non-linear dispersion relation. In 1995 Unruh showed that they are not sensitive in this respect, in spite of the fact that phonon propagation near the (acoustic) horizon drastically differs from that of photons. In 2000 the same analogy was used to establish the robustness of the spectrum of primordial density fluctuations in inflationary models. This analogy is currently stimulating research for experimenting Hawking radiation. Finally it could also be a useful guide for going beyond the semi-classical description of black hole evaporation.

Hawking radiation of charged fermions from accelerating and rotating black holes with generalized uncertainty principle

2019 ◽  
Vol 28 (08) ◽  
pp. 1950102
Author(s):  
Muhammad Rizwan ◽  
Khalil Ur Rehman
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Uncertainty Principle ◽  
Hawking Radiation ◽  
Generalized Uncertainty Principle ◽  
Hawking Temperature ◽  
Black Hole Evaporation ◽  
Rotating Black Holes ◽  
Gravity Effects ◽  
Made In

By considering the quantum gravity effects based on generalized uncertainty principle, we give a correction to Hawking radiation of charged fermions from accelerating and rotating black holes. Using Hamilton–Jacobi approach, we calculate the corrected tunneling probability and the Hawking temperature. The quantum corrected Hawking temperature depends on the black hole parameters as well as quantum number of emitted particles. It is also seen that a remnant is formed during the black hole evaporation. In addition, the corrected temperature is independent of an angle [Formula: see text] which contradicts the claim made in the literature.

scholarly journals Planckian physics comes into play at Planckian distance from horizon

2022 ◽  
Vol 2022 (1) ◽  
Author(s):  
Pei-Ming Ho ◽  
Hikaru Kawai ◽  
Yuki Yokokura
Keyword(s):  
Black Hole ◽  
Gravitational Collapse ◽  
Hawking Radiation ◽  
Effective Theory ◽  
Planck Length ◽  
Black Hole Evaporation ◽  
Higher Derivative ◽  
The Creation ◽  
Transition Amplitudes

Abstract In the background of a gravitational collapse, we compute the transition amplitudes for the creation of particles for distant observers due to higher-derivative interactions in addition to Hawking radiation. The amplitudes grow exponentially with time and become of order 1 when the collapsing matter is about a Planck length outside the horizon. As a result, the effective theory breaks down at the scrambling time, invalidating its prediction of Hawking radiation. Planckian physics comes into play to decide the fate of black-hole evaporation.

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.

BARYOGENESIS FROM BLACK HOLE EVAPORATION

1995 ◽  
Vol 04 (04) ◽  
pp. 517-529 ◽  
Author(s):  
A.S. MAJUMDAR ◽  
P. DAS GUPTA ◽  
R.P. SAXENA
Keyword(s):  
Phase Transition ◽  
Black Holes ◽  
Black Hole ◽  
Hawking Radiation ◽  
Baryon Asymmetry ◽  
False Vacuum ◽  
Black Hole Evaporation ◽  
Inflationary Phase ◽  
The Universe

The possibility of baryogenesis through the evaporation of black holes formed during extended inflation is explored. These black holes are produced due to the collapse of trapped regions of false vacuum during the inflationary phase transition. Immediately after formation, the accretion of mass from the surrounding hot radiation bath in the universe is shown to be an important effect. This causes the lifetime of the black holes to be considerably elongated before they evaporate out through the process of Hawking radiation. It is shown that a sufficient number of black holes last up to well past the electroweak era and hence contribute to the surviving baryon asymmetry in the universe.

Hawking radiation of analogous acoustic black holes

2020 ◽  
Vol 35 (28) ◽  
pp. 2050236
Author(s):  
Shiwei Zhou ◽  
Kui Xiao
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Hawking Radiation ◽  
Emission Rate ◽  
Massless Scalar ◽  
Massless Scalar Field ◽  
Spherically Symmetric ◽  
Sound Waves ◽  
Flowing Fluid ◽  
Acoustic Black Holes

Propagation of sound waves in a flowing fluid can be viewed as a minimally coupled massless scalar field propagating in curved spacetime. The analogue Hawking radiation from a spherically symmetric acoustic black hole and a (2 + 1)-dimensional rotating acoustic black hole are investigated respectively in Damour–Ruffini’s method. The emission rate and Hawking temperature are obtained, which are related to acoustic black holes parameter.

scholarly journals Minimal length and the flow of entropy from black holes

2018 ◽  
Vol 27 (14) ◽  
pp. 1847028 ◽  
Author(s):  
Ana Alonso-Serrano ◽  
Mariusz P. Da̧browski ◽  
Hussain Gohar
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Quantum Gravity ◽  
Uncertainty Principle ◽  
Hawking Radiation ◽  
Generalized Uncertainty Principle ◽  
Minimal Length ◽  
Evaporation Process ◽  
Black Hole Evaporation ◽  
The Impact

The existence of a minimal length, predicted by different theories of quantum gravity, can be phenomenologically described in terms of a generalized uncertainty principle. We consider the impact of this quantum gravity motivated effect onto the information budget of a black hole and the sparsity of Hawking radiation during the black hole evaporation process. We show that the information is not transmitted at the same rate during the final stages of the evaporation, and that the Hawking radiation is not sparse anymore when the black hole approaches the Planck mass.

ON THE EFFECT OF ENERGY CONSERVATION ON BLACK HOLE EVAPORATION

2013 ◽  
Vol 22 (07) ◽  
pp. 1350037 ◽  
Author(s):  
R. TORRES ◽  
F. FAYOS ◽  
O. LORENTE-ESPÍN
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Energy Conservation ◽  
Hawking Radiation ◽  
Scattered Radiation ◽  
Emission Rate ◽  
Information Loss ◽  
Evaporation Process ◽  
Black Hole Evaporation ◽  
Information Loss Paradox

We consider the emission of Hawking radiation by black holes as a consequence of a tunneling process. By requiring energy conservation in the derivation of the emission rate we get a well-known deviation from an exact thermal spectrum. A model that takes into account the implications of energy conservation, as well as the back-scattered radiation, is then constructed in order to describe the evolution of black holes as they evaporate. The evaporation process in this model is compared with the results in the standard "thermal" approximation. This allows us to point out the relevance that energy conservation might have in the last stages of black hole evaporation. We also comment about the possible implications of energy conservation in the information loss paradox.

scholarly journals Black-Hole evaporation and quantum-depletion in Bose–Einstein condensates

2020 ◽  
pp. 2150006
Author(s):  
Ivan Arraut
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Temperature Regime ◽  
Hawking Radiation ◽  
Einstein Condensate ◽  
Zero Temperature ◽  
Black Hole Evaporation ◽  
Bose Einstein Condensate ◽  
Bose Einstein ◽  
Bogoliubov Transformations

We study the analogy between the Hawking radiation in Black-Holes and the quantum depletion process of a Bose–Einstein condensate by using the Bogoliubov transformations method. We find that the relation between the Bogoliubov coefficients is similar in both cases (in the appropriate regimes). We then connect the condensate variables with those associated to the Black-Hole, demonstrating then that the zero temperature regime of the condensate is equivalent to the existence of an event horizon in gravity.

scholarly journals BLACK HOLE GEOMETRIES IN NONCOMMUTATIVE STRING THEORY

2006 ◽  
Vol 21 (30) ◽  
pp. 6087-6114 ◽  
Author(s):  
SUPRIYA KAR ◽  
SUMIT MAJUMDAR
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Gauge Theory ◽  
String Theory ◽  
Hawking Radiation ◽  
Effective Theory ◽  
Effective Gravity ◽  
Noncommutative Gauge Theory ◽  
Em Field ◽  
Hole Geometry

We obtain a generalized Schwarzschild (GS) and a generalized Reissner–Nordstrom (GRN) black hole geometries in 3+1 dimensions, in a noncommutative string theory. In particular, we consider an effective theory of gravity on a curved D3-brane in presence of an electromagnetic (EM) field. Two different length scales, inherent in its noncommutative counterpart, are exploited to obtain a theory of effective gravity coupled to an U(1) noncommutative gauge theory to all orders in Θ. It is shown that the GRN-black hole geometry, in the Planckian regime, reduces to the GS-black hole. However in the classical regime it may be seen to govern both the Reissner–Nordstrom and the Schwarzschild geometries. The emerging notion of 2D black holes evident in the framework are analyzed. It is argued that the D-string in the theory may be described by the near horizon 2D black hole geometry, in the gravity decoupling limit. Finally, our analysis explains the nature of the effective force derived from the nonlinear EM-field and accounts for the Hawking radiation phenomenon in the formalism.

scholarly journals Islands and stretched horizon

2021 ◽  
Vol 2021 (7) ◽  
Author(s):  
Yoshinori Matsuo
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Hawking Radiation ◽  
Entanglement Entropy ◽  
Total System ◽  
Island Rule ◽  
Asymptotically Flat ◽  
Flat Spacetime ◽  
Ads Spacetime ◽  
Hole Geometry

Abstract Recently it was proposed that the entanglement entropy of the Hawking radiation contains the information of a region including the interior of the event horizon, which is called “island.” In studies of the entanglement entropy of the Hawking radiation, the total system in the black hole geometry is separated into the Hawking radiation and black hole. In this paper, we study the entanglement entropy of the black hole in the asymptotically flat Schwarzschild spacetime. Consistency with the island rule for the Hawking radiation implies that the information of the black hole is located in a different region than the island. We found an instability of the island in the calculation of the entanglement entropy of the region outside a surface near the horizon. This implies that the region contains all the information of the total system and the information of the black hole is localized on the surface. Thus the surface would be interpreted as the stretched horizon. This structure also resembles black holes in the AdS spacetime with an auxiliary flat spacetime, where the information of the black hole is localized at the interface between the AdS spacetime and the flat spacetime.

Sign in / Sign up

Export Citation Format

Share Document