Great breakthrough in solving black hole information paradox took place when semiclassical island rule for entanglement entropy of Hawking radiation was proposed recent years. Up to now, most papers which discussed asymptotic flat with $D \ge 4$ focus on eternal hole. In this paper, we take one more step further by discussing "in" vacuum state describes one-sided asymptotically formed gravitational collapse 4$. We find that $I$ emerges at late time and saves bound. And boundary $\partial I$...

In this paper we systematically study a recently proposed model of spherically symmetric polymer black/white holes by Bodendorfer, Mele, and M\"unch (BMM), which generically possesses five free parameters. However, find that, out these parameters, only three independent combinations them are physical uniquely determine the local global properties spacetimes. After exploring whole 3-dimensional (3D) parameter space, show that has very rich physics, depending on choice various possibilities...

We reconsider $D\ensuremath{\ge}4$ dimensional asymptotically flat eternal Schwarzschild black hole and focus on the situation where inner boundary of radiation region is chosen to be near horizon (i.e., $\ensuremath{\beta}\ensuremath{\ll}1$). The tension between near-horizon condition short-distance approximation emerges in large dimensions [K. Hashimoto, N. Iizuka, Y. Matsuo, J. High Energy Phys. 06 (2020) 085]. remove this by introducing a more proper condition; thus, resulting island...

A bstract It was proposed recently that the fine-grained entropy of Hawking radiation can be expressed by semiclassical island formula, which reproduces unitary Page curve. In this paper, we choose “in” vacuum state and apply quantum extremal surface construction to study curve for step-function Vaidya model evaporating black holes in four dimensions, is produced spherical null shells. Metrics three regions spacetimes are obtained. addition, entanglement islands at very late times studied....

Abstract In this paper, we consider the Böhmer–Vandersloot (BV) model of loop quantum black holes obtained from improved dynamics approach. We adopt Saini–Singh gauge, in which it was found analytically that BV spacetime is geodesically complete. show black/white hole horizons do not exist complete spacetime. Instead, there exists only an infinite number transition surfaces, always separate trapped regions anti-trapped ones. Comments on approach adopted other models are also given.

For a pair of incompatible quantum measurements, the total uncertainty can be bounded by state-independent constant. However, such bound violated if system is entangled with another (called memory); correlation between systems reduce measurement uncertainty. On other hand, in curved spacetime, presence Hawking radiation increase measurement. The interplay spacetime has become an interesting arena for studying relations. Here we demonstrate that bounds entropic relations, memory, formulated...

Quantum many-body problem with exponentially large degrees of freedom can be reduced to a tractable computational form by neural network method \cite{CT}. The power deep (DNN) based on learning is clarified mapping it renormalization group (RG), which may shed lights holographic principle identifying sequence RG transformations the AdS geometry. In this essay, we show that any reflects process has intrinsic hyperbolic geometry, and discuss structure entanglement encoded in graph DNN. We find...

Quantum information theory and holography play central roles in our understanding of quantum gravity. Exploring their connections will lead to profound effects on modern physics is, thus, a key challenge for present experiments. In this paper, we investigate recent conjectured connection between reduced fidelity susceptibility holographic complexity (denoted as the RFS/HC duality). We give quantitative proof duality by performing both field theoretical computations. addition,...

We systematically study the top-down model of loop quantum black holes (LQBHs), recently derived by Alesci, Bahrami and Pranzetti (ABP). To understand structure model, we first derive several well-known LQBH solutions taking proper limits. These include B\"ohmer-Vandersloot Ashtekar-Olmedo-Singh models, which were all obtained so-called bottom-up polymerizations within framework minisuperspace quantizations. Then, ABP find that inverse volume corrections become important only when radius...

We present how the thermal geometry emerges from CFT at finite temperature by using truncated entanglement renormalization network, cMERA. For case of $2d$ CFT, reduced is BTZ black hole or AdS as expectation. In order to determine which spacetimes prefer form, we propose a cMERA description Hawking-Page phase transition. Our proposal in agreement with picture recent proposed surface/state correspondence.

A bstract In this paper, we extend the method of calculating entanglement entropy Hawking radiation black holes using “in” vacuum state, which describes one-sided asymptotically flat neutral hole formed by gravitational collapse, to dynamic charged holes. We explore influence charge on position boundary island ∂I and Page time. Due their distinct geometric structures, discuss non-extremal extremal separately. cases, emergence saves bound at late times, satisfies curve. Moreover, also find...

A concept of measuring the quantum distance between two different states which is called information metric presented. The holographic principle (AdS/CFT) suggests that $G_{\lambda\lambda}$ perturbed state and unperturbed in field theory has a dual description classical gravity. In this work we calculate to conical defect geometry show it $n$ times one its covering space. We also give check for our result gravity side. Meanwhile, was argued codimension-one surface spacetime satisfies...

In this paper, we study the quantum geometric effects near locations where classical black hole horizons used to appear in Einstein's theory, within framework of an improved dynamic approach, which internal region a is modeled by Kantowski-Sachs (KS) spacetime and two polymerization parameters are functions phase space variables. Our detailed analysis shows that so strong white effective theory do not exist at all instead replaced transition surfaces, across metric coefficients their...

In this paper we analyse and discuss 2D Jackiw-Teitelboim (JT) gravity coupled to primary fermion fields in asymptotically anti-de Sitter (AdS) spacetimes. We get a particular solution of the massless Dirac field outside extremal black hole horizon find for dilaton JT gravity. Two dimensional spacetime is conformally flat, calculate two point correlators under Weyl transformations. The key work present standard technique which called resolvent rather than CFT methods. redefine terms...

We study a conjectured correspondence between any codimension two convex surface and quantum state (SS-duality for short). By generalizing thermofield double formalism to continuum version of the multi-scale entanglement renormalization ansatz (cMERA) using SS-duality, we show that thermal geometries naturally emerge as result hidden boundary CFTs. therefore propose general framework geometry from CFT at finite temperature. As an example, case $2d$ is considered. calculate its information...

Unitary evolution makes pure state on one Cauchy surface evolve to another surface. Outgoing Hawking radiation is the only subsystem late The requirement that should be amounts requiring purity of when total system pure. We will see this lead firewall even in flat spacetime, and thus invalid. Information either stored entanglement between field modes inside black hole outgoing or correlation geometry singularity resolved by quantum gravity effects. give a simple argument semi-classical...

Loop quantum cosmology has achieved great successes, in which the polymerization plays a crucial role. In particular, phase-space-variable dependent turns out to be unique one that leads consistent quantization of homogeneous and isotropic universe. However, when applying same scheme black holes, it meets resistances, Kantowski-Sachs (KS) gauge is adopted. this paper, we continue study effects near location classical hole horizon used be, from point view effective loop gravity KS gauge. find...

In this paper, we consider the B\"ohmer-Vandersloot (BV) model of loop quantum black holes obtained from improved dynamics approach. We adopt Saini-Singh gauge, in which it was found analytically that BV spacetime is geodesically complete. show black/white hole horizons do not exist complete spacetime. Instead, there exists only an infinite number transition surfaces, always separate trapped regions anti-trapped ones. Comments on approach adopted other models are also given.

In this paper, we extend the method of calculating entanglement entropy Hawking radiation black holes using "in" vacuum state, which describes one-sided asymptotically flat neutral hole formed by gravitational collapse, to dynamic charged holes. We explore influence charge on position boundary island $\partial I$ and Page time. Due their distinct geometric structures, discuss non-extremal extremal separately. cases, emergence saves bound at late times, satisfies curve. Moreover, also find...

It was proposed recently that the fine-grained entropy of Hawking radiation can be expressed by semiclassical island formula, which reproduces unitary Page curve. In this paper, we choose ``in'' vacuum state and apply quantum extremal surface construction to study curve for step-function Vaidya model evaporating black holes in four dimensions, is produced spherical null shells. Metrics three regions spacetimes are obtained. addition, entanglement islands at very late times studied. When...

We systematically study the top-down model of loop quantum black holes (LQBHs), recently derived by Alesci, Bahrami and Pranzetti (ABP). To understand structure model, we first derive several well-known LQBH solutions taking proper limits. These include Böhmer-Vandersloot Ashtekar-Olmedo-Singh models, which were all obtained so-called bottom-up polymerizations within framework minisuperspace quantizations. Then, ABP find that inverse volume corrections become important only when radius...

We reconsider $D\geq4$ dimensional asymptotically flat eternal Schwarzschild black hole, and focus on the situation where inner boundary of radiation region is chosen to be near horizon (i.e. $β\ll1$). The tension between near-horizon condition short-distance approximation emerges in large dimensions $[JHEP 06 (2020) 085]$. remove this by introducing a more proper condition, thus resulting island solution well-behaved any spacetime. Interestingly, novel constraint obtained as required...