Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
4.9
2.1
Journals
Entropy
Special Issues
The Black Hole Information Problem
entropy-logo
Submit to Entropy Review for Entropy Propose a Special Issue

Journal Menu

► Journal Menu

Journal Browser

► Journal Browser
share announcement

The Black Hole Information Problem

A special issue of Entropy (ISSN 1099-4300). This special issue belongs to the section "Astrophysics, Cosmology, and Black Holes".

Deadline for manuscript submissions: closed (31 October 2024) | Viewed by 6041

Special Issue Editors

Prof. Dr. Stephen Hsu

E-Mail Website
Guest Editor
Department of Physics and Astronomy, Michigan State University, Michigan, MI 48823, USA
Interests: theoretical physics; quantum mechanics; particle physics; quantum field theory; cosmology; black holes
Prof. Dr. Xavier Calmet

E-Mail Website
Guest Editor
Department of Physics and Astronomy, University of Sussex, Sussex BN1 4GE, UK
Interests: theoretical physics; quantum physics; quantum gravity; black holes; cosmology; quantum field theory
Special Issues, Collections and Topics in MDPI journals
Dr. Roberto Casadio

E-Mail Website
Guest Editor
Department of Physics and Astronomy, University of Bologna, 40126 Bologna, Italy
Interests: quantum aspects of the gravitational interaction; gravitational collapse; black hole formation and evolution

Special Issue Information

Dear Colleagues,

In 1976, Stephen Hawking argued, based on the nature of the black hole radiation which he discovered, that there is a fundamental conflict between gravity and quantum mechanics. He argued that black hole evaporation cannot be unitary; it causes a pure initial quantum state to evolve into a mixed state. For almost fifty years, physicists have attempted to resolve this problem.

Recently, it has been emphasized that the quantum state of the spacetime geometry (i.e., graviton field) external to the black hole horizon carries quantum information which is dependent on the internal state of the black hole. As a consequence, the No Hair Theorem describing black holes is violated by quantum effects (“quantum hair”). More generally, it has also been proposed (“information holography”) that all of the quantum information describing the bulk of spacetime can be recovered, in principle, through precise measurements of the graviton and matter fields at the asymptotic boundary of spacetime.

This Special Issue aims to be a forum for a discussion of black hole information, with emphasis on recent developments such as, but not limited to, those described above.

Contributions on the following topics are particularly welcome: quantum hair from black holes, information holography, influence on Hawking radiation mediated by quantum effects in the horizon region, encoding of quantum information in Hawking radiation, entropy of Hawking radiation, the role of macroscopic superposition states in the quantum evolution of black holes, the role of quantum foundations in understanding black hole information, and novel scenarios for remnants.

Prof. Dr. Stephen Hsu
Prof. Dr. Xavier Calmet
Dr. Roberto Casadio
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Entropy is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • black holes
  • quantum information
  • unitarity
  • Hawking radiation
  • quantum foundations
  • decoherence
  • AdS/CFT duality
  • quantum gravity
  • quantum fields in curved space

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Published Papers (5 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

17 pages, 899 KiB  
Article
Corrected Thermodynamics of Black Holes in f(R) Gravity with Electrodynamic Field and Cosmological Constant
by Mou Xu, Yuying Zhang, Liu Yang, Shining Yang and Jianbo Lu
Entropy 2024, 26(10), 868; https://doi.org/10.3390/e26100868 - 15 Oct 2024
Viewed by 635
Abstract
The thermodynamics of black holes (BHs) and their corrections have become a hot topic in the study of gravitational physics, with significant progress made in recent decades. In this paper, we study the thermodynamics and corrections of spherically symmetric BHs in models [...] Read more.
The thermodynamics of black holes (BHs) and their corrections have become a hot topic in the study of gravitational physics, with significant progress made in recent decades. In this paper, we study the thermodynamics and corrections of spherically symmetric BHs in models f(R)=R+αR2 and f(R)=R+2γR+8Λ under the f(R) theory, which includes the electrodynamic field and the cosmological constant. Considering thermal fluctuations around equilibrium states, we find that, for both f(R) models, the corrected entropy is meaningful in the case of a negative cosmological constant (anti-de Sitter–RN spacetime) with Λ=−1. It is shown that when the BHs’ horizon radius is small, thermal fluctuations have a more significant effect on the corrected entropy. Using the corrected entropy, we derive expressions for the relevant corrected thermodynamic quantities (such as Helmholtz free energy, internal energy, Gibbs free energy, and specific heat) and calculate the effects of the correction terms. The results indicate that the corrections to Helmholtz free energy and Gibbs free energy, caused by thermal fluctuations, are remarkable for small BHs. In addition, we explore the stability of BHs using specific heat. The study reveals that the corrected BH thermodynamics exhibit locally stable for both models, and corrected systems undergo a Hawking–Page phase transition. Considering the requirement on the non-negative volume of BHs, we also investigate the constraint on the EH radius of BHs. Full article
(This article belongs to the Special Issue The Black Hole Information Problem)
►▼ Show Figures

Figure 1

17 pages, 352 KiB  
Article
Look Beyond Additivity and Extensivity of Entropy for Black Hole and Cosmological Horizons
by Mariusz P. Da̧browski
Entropy 2024, 26(10), 814; https://doi.org/10.3390/e26100814 - 25 Sep 2024
Cited by 1 | Viewed by 571
Abstract
We present a comparative analysis of the plethora of nonextensive and/or nonadditive entropies which go beyond the standard Boltzmann–Gibbs formulation. After defining the basic notions of additivity, extensivity, and composability, we discuss the properties of these entropies and their mutual relations, if they [...] Read more.
We present a comparative analysis of the plethora of nonextensive and/or nonadditive entropies which go beyond the standard Boltzmann–Gibbs formulation. After defining the basic notions of additivity, extensivity, and composability, we discuss the properties of these entropies and their mutual relations, if they exist. The results are presented in two informative tables that are of strong interest to the gravity and cosmology community in the context of the recently intensively explored horizon entropies for black hole and cosmological models. Gravitational systems admit long-range interactions, which usually lead to a break of the standard additivity rule for thermodynamic systems composed of subsystems in Boltzmann–Gibbs thermodynamics. The features of additivity, extensivity, and composability are listed systematically. A brief discussion on the validity of the notion of equilibrium temperature for nonextensive systems is also presented. Full article
(This article belongs to the Special Issue The Black Hole Information Problem)
10 pages, 331 KiB  
Article
Lagrangian Partition Functions Subject to a Fixed Spatial Volume Constraint in the Lovelock Theory
by Mengqi Lu and Robert B. Mann
Entropy 2024, 26(4), 291; https://doi.org/10.3390/e26040291 - 27 Mar 2024
Cited by 1 | Viewed by 985
Abstract
We evaluate here the quantum gravity partition function that counts the dimension of the Hilbert space of a simply connected spatial region of a fixed proper volume in the context of Lovelock gravity, generalizing the results for Einstein gravity. It is found that [...] Read more.
We evaluate here the quantum gravity partition function that counts the dimension of the Hilbert space of a simply connected spatial region of a fixed proper volume in the context of Lovelock gravity, generalizing the results for Einstein gravity. It is found that there are sphere saddle metrics for a partition function at a fixed spatial volume in Lovelock theory. Those stationary points take exactly the same forms as in Einstein gravity. The logarithm of Z corresponding to a zero effective cosmological constant indicates that the Bekenstein–Hawking entropy of the boundary area and that corresponding to a positive effective cosmological constant points to the Wald entropy of the boundary area. We also show the existence of zeroth-order phase transitions between different vacua, a phenomenon distinct from Einstein gravity. Full article
(This article belongs to the Special Issue The Black Hole Information Problem)
►▼ Show Figures

Figure 1

15 pages, 752 KiB  
Article
Tunneling between Multiple Histories as a Solution to the Information Loss Paradox
by Pisin Chen, Misao Sasaki, Dong-han Yeom and Junggi Yoon
Entropy 2023, 25(12), 1663; https://doi.org/10.3390/e25121663 - 15 Dec 2023
Cited by 2 | Viewed by 1190
Abstract
The information loss paradox associated with black hole Hawking evaporation is an unresolved problem in modern theoretical physics. In a recent brief essay, we revisited the evolution of the black hole entanglement entropy via the Euclidean path integral (EPI) of the quantum state [...] Read more.
The information loss paradox associated with black hole Hawking evaporation is an unresolved problem in modern theoretical physics. In a recent brief essay, we revisited the evolution of the black hole entanglement entropy via the Euclidean path integral (EPI) of the quantum state and allow for the branching of semi-classical histories along the Lorentzian evolution. We posited that there exist at least two histories that contribute to EPI, where one is an information-losing history, while the other is an information-preserving one. At early times, the former dominates EPI, while at the late times, the latter becomes dominant. By doing so, we recovered the essence of the Page curve, and thus, the unitarity, albeit with the turning point, i.e., the Page time, much shifted toward the late time. In this full-length paper, we fill in the details of our arguments and calculations to strengthen our notion. One implication of this modified Page curve is that the entropy bound may thus be violated. We comment on the similarity and difference between our approach and that of the replica wormholes and the islands’ conjectures. Full article
(This article belongs to the Special Issue The Black Hole Information Problem)
►▼ Show Figures

Figure 1

24 pages, 1584 KiB  
Article
Discreteness Unravels the Black Hole Information Puzzle: Insights from a Quantum Gravity Toy Model
by Alejandro Perez and Sami Viollet
Entropy 2023, 25(11), 1479; https://doi.org/10.3390/e25111479 - 25 Oct 2023
Cited by 1 | Viewed by 1509
Abstract
The black hole information puzzle can be resolved if two conditions are met. The first is that the information about what falls inside a black hole remains encoded in degrees of freedom that persist after the black hole completely evaporates. These degrees of [...] Read more.
The black hole information puzzle can be resolved if two conditions are met. The first is that the information about what falls inside a black hole remains encoded in degrees of freedom that persist after the black hole completely evaporates. These degrees of freedom should be capable of purifying the information. The second is if these purifying degrees of freedom do not significantly contribute to the system’s energy, as the macroscopic mass of the initial black hole has been radiated away as Hawking radiation to infinity. The presence of microscopic degrees of freedom at the Planck scale provides a natural mechanism for achieving these two conditions without running into the problem of the large pair-creation probabilities of standard remnant scenarios. In the context of Hawking radiation, the first condition implies that correlations between the in and out Hawking partner particles need to be transferred to correlations between the microscopic degrees of freedom and the out partners in the radiation. This transfer occurs dynamically when the in partners reach the singularity inside the black hole, entering the UV regime of quantum gravity where the interaction with the microscopic degrees of freedom becomes strong. The second condition suggests that the conventional notion of the vacuum’s uniqueness in quantum field theory should fail when considering the full quantum gravity degrees of freedom. In this paper, we demonstrate both key aspects of this mechanism using a solvable toy model of a quantum black hole inspired by loop quantum gravity. Full article
(This article belongs to the Special Issue The Black Hole Information Problem)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-5
Back to TopTop