Black holes: Quantum trapping and singularity resolution

2006 ◽  
Vol 84 (6-7) ◽  
pp. 591-597
Author(s):  
V Husain ◽  
O Winkler
Keyword(s):  
Black Hole ◽  
Quantum Dynamics ◽  
Recent Progress ◽  
Late Time ◽  
Time Behaviour ◽  
Initial State ◽  
Quantum Black Hole ◽  
Black Hole Radiation ◽  
Singularity Resolution ◽  
Physical Result

We describe recent progress on the problem of gravitational collapse in quantum gravity. The model we study is the gravity-scalar field theory in spherical symmetry, which is the original setting for Hawking's semiclassical work on black-hole radiation. We present an approach to full quantization of this model in a Hamiltonian framework, with a view to understanding the late time behaviour of collapsing matter. We give operator realizations of curvature and null expansion variables. The first of these operators has a bounded spectrum indicating curvature singularity avoidance; the second provides a "quantum trapping" criterion for detecting whether a quantum state describes a black hole. It leads to the physical result that the boundary of a quantum black hole is subject to quantum fluctuations. We describe an approach to quantum dynamics, whereby an initial state can be evolved, and tracked to the point of quantum trapping and beyond.PACS Nos.: 04.60.–m, 04.60.Ds, 04.70.Dy

More on extracting information about the initial state from the black hole radiation

2018 ◽  
Vol 33 (19) ◽  
pp. 1850108
Author(s):  
Hossein Ghaforyan ◽  
Somayyeh Shoorvazi ◽  
Alireza Sepehri ◽  
Tooraj Ghaffary
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Density Matrix ◽  
Quantum Entanglement ◽  
Event Horizon ◽  
Initial State ◽  
Black Hole Radiation ◽  
Total Information ◽  
Quantum Treatment ◽  
Collapse Process

Recently, some authors showed that a classical collapse scenario ignores this richness of information in the resulting spectrum and a consistent quantum treatment of the entire collapse process might allow us to retrieve much more information from the spectrum of the final radiation. We confirm these results and show that by considering the quantum entanglement between metrics, we can uncover information of black holes. In our model, a density matrix is defined for the spaces, both inside and outside of the event horizon. These inside and outside spaces of black holes are obtained by tracing from a bigger space. An observer that lives in this big space can recover total information regarding the inside and outside of black hole.

scholarly journals Probing black hole microstate evolution with networks and random walks

2020 ◽  
Vol 8 (5) ◽  
Author(s):  
Anthony Charles ◽  
Daniel Mayerson
Keyword(s):  
Hilbert Space ◽  
Black Hole ◽  
Time Evolution ◽  
Network Theory ◽  
Quantum Tunneling ◽  
Emergent Property ◽  
Late Time ◽  
Time Behavior ◽  
Relative Importance ◽  
Time Behaviour

We model black hole microstates and quantum tunneling transitions between them with networks and simulate their time evolution using well-established tools in network theory. In particular, we consider two models based on Bena-Warner three-charge multi-centered microstates and one model based on the D1-D5 system; we use network theory methods to determine how many centers (or D1-D5 string strands) we expect to see in a typical late-time state. We find three distinct possible phases in parameter space for the late-time behaviour of these networks, which we call ergodic, trapped, and amplified, depending on the relative importance and connectedness of microstates. We analyze in detail how these different phases of late-time behavior are related to the underlying physics of the black hole microstates. Our results indicate that the expected properties of microstates at late times cannot always be determined simply by entropic arguments; typicality is instead a highly non-trivial, emergent property of the full Hilbert space of microstates.

scholarly journals Improved effective dynamics of loop-quantum-gravity black hole and Nariai limit

2021 ◽  
Author(s):  
Muxin Han ◽  
Hongguang Liu
Keyword(s):  
Black Hole ◽  
Quantum Gravity ◽  
Degrees Of Freedom ◽  
Loop Quantum Gravity ◽  
Late Time ◽  
White Hole ◽  
Quantum Black Hole ◽  
Effective Dynamics ◽  
Symmetric Quantum ◽  
Space Formulation

Abstract We propose a new model of the spherical symmetric quantum black hole in the reduced phase space formulation. We deparametrize gravity by coupling to the Gaussian dust which provides the material coordinates. The foliation by dust coordinates covers both the interior and exterior of the black hole. After the spherical symmetry reduction, our model is a 1+1 dimensional field theory containing infinitely many degrees of freedom. The effective dynamics of the quantum black hole is generated by an improved physical Hamiltonian ${\bf H}_\Delta$. The holonomy correction in ${\bf H}_\Delta$ is implemented by the $\bar{\mu}$-scheme regularization with a Planckian area scale $\Delta$ (which often chosen as the minimal area gap in Loop Quantum Gravity). The effective dynamics recovers the semiclassical Schwarzschild geometry at low curvature regime and resolves the black hole singularity with Planckian curvature, e.g. $R_{\mu\nu\rho\sigma}R^{\mu\nu\rho\sigma}\sim 1/{\Delta}^2$. Our model predicts that the evolution of the black hole at late time reaches the charged Nariai geometry ${\rm dS}_2\times S^2$ with Planckian radii $\sim \sqrt{\Delta}$. The Nariai geometry is stable under linear perturbations but may be unstable by nonperturbative quantum effects. Our model suggests the existence of quantum tunneling of the Nariai geometry and a scenario of black-hole-to-white-hole transition.

scholarly journals Entanglement wedge reconstruction and the information paradox

2020 ◽  
Vol 2020 (9) ◽  
Author(s):  
Geoffrey Penington
Keyword(s):  
Black Hole ◽  
Hawking Radiation ◽  
Entanglement Entropy ◽  
State Dependence ◽  
Absorbing Boundary Conditions ◽  
Late Time ◽  
Mixed States ◽  
Initial State ◽  
Absorbing Boundary ◽  
The Past

Abstract When absorbing boundary conditions are used to evaporate a black hole in AdS/CFT, we show that there is a phase transition in the location of the quantum Ryu-Takayanagi surface, at precisely the Page time. The new RT surface lies slightly inside the event horizon, at an infalling time approximately the scrambling time β/2πlogSBH into the past. We can immediately derive the Page curve, using the Ryu-Takayanagi formula, and the Hayden-Preskill decoding criterion, using entanglement wedge reconstruction. Because part of the interior is now encoded in the early Hawking radiation, the decreasing entanglement entropy of the black hole is exactly consistent with the semiclassical bulk entanglement of the late-time Hawking modes, despite the absence of a firewall.By studying the entanglement wedge of highly mixed states, we can understand the state dependence of the interior reconstructions. A crucial role is played by the existence of tiny, non-perturbative errors in entanglement wedge reconstruction. Directly after the Page time, interior operators can only be reconstructed from the Hawking radiation if the initial state of the black hole is known. As the black hole continues to evaporate, reconstructions become possible that simultaneously work for a large class of initial states. Using similar techniques, we generalise Hayden-Preskill to show how the amount of Hawking radiation required to reconstruct a large diary, thrown into the black hole, depends on both the energy and the entropy of the diary. Finally we argue that, before the evaporation begins, a single, state-independent interior reconstruction exists for any code space of microstates with entropy strictly less than the Bekenstein-Hawking entropy, and show that this is sufficient state dependence to avoid the AMPSS typical-state firewall paradox.

A UV complete picture of black hole conforming to low energy effective field theory

2018 ◽  
Vol 33 (36) ◽  
pp. 1850219
Author(s):  
Biplab Paik
Keyword(s):  
Field Theory ◽  
Black Hole ◽  
Effective Field Theory ◽  
Effective Field ◽  
Radiation Process ◽  
Quantum Black Hole ◽  
Classical Geometry ◽  
Characteristic Radius ◽  
Hole Geometry ◽  
Principle Of Causality

In this paper, we propose a UV complete, quantum improved picture of a black hole geometry that conforms to the IR gravity of effective field theory. Our work builds on identifying an effective space-distributed notion of black hole fluid in quantum improved regular Einstein gravity and its theoretical correspondence with a cosmology inspired power law fluctuation of matter. Hence, we make use of phenomenological asymptotic scales of matter fluctuation in static space to consequently derive a UV complete line-element of black hole space–time. In this appraisal, it gets explicit how principle of causality is preserved even while there is an effective spread of black hole fluid across horizon(s). Gravity changes from its conventional classical geometry-state to a quantum masked profile across a hypersurface of characteristic radius [Formula: see text]. We make analyses that probe the newly proposed quantum improved gravity in the contexts of regularity of Einstein fields, complete predictability of Hawking radiation process, and first law of black hole thermodynamics. It emerges that quantum black hole geometry self-regulates a regular timelike core that is abide by every quantum theoretical constraint while being flat around its center.

scholarly journals Quantum black hole formation in the BFSS matrix model

2015 ◽  
Vol 2015 (7) ◽  
Author(s):  
Sinya Aoki ◽  
Masanori Hanada ◽  
Norihiro Iizuka
Keyword(s):  
Black Hole ◽  
Matrix Model ◽  
Hole Formation ◽  
Quantum Black Hole ◽  
Black Hole Formation

Black-Hole Radiation

1985 ◽  
Vol 85 ◽  
pp. 271-278 ◽  
Author(s):  
Tsung Dao Lee
Keyword(s):  
Black Hole ◽  
Black Hole Radiation
Sign in / Sign up

Export Citation Format

Share Document