Search

The concept of the generalized entanglement wedge was recently proposed by Bousso and Penington, which states that any bulk gravitational region $a$ possesses an associated generalized entanglement wedge $E(a)\supset a$ on a static Cauchy surface $M$ in general gravitational spacetimes, where $E(a)$ may contain an entanglement island $I(a)$. It suggests that the fine-grained entropy for bulk region $a$ is given by the generalized entropy $S_{\text{gen}}(E(a))$. Motivated by this proposal, we extend the quantum bit thread description to general gravitational spacetimes, no longer limited to the AdS spacetime. By utilizing the convex optimization techniques, a dual flow description for the generalized entropy $S_{\text{gen}}(E(a))$ of a bulk gravitational region $a$ is established on the static Cauchy surface $M$, such that $S_{\text{gen}}(E(a))$ is equal to the maximum flux of any flow that starts from the boundary $\partial M$ and ends at bulk region $a$, or equivalently, the maximum number of bit threads that connect the boundary $\partial M$ to the bulk region $a$. In addition, the nesting property of flows is also proved. Thus the basic properties of the entropy for bulk regions, i.e. the monotonicity, subadditivity, Araki-Lieb inequality and strong subadditivity, can be verified from flow perspectives by using properties of flows, such as the nesting property. Moreover, in max thread configurations, we find that there exists some lower bounds on the bulk entanglement entropy of matter fields in the region $E(a)\setminus a$, particularly on an entanglement island region $I(a) \subset (E(a)\setminus a)$, as required by the existence of a nontrivial generalized entanglement wedge. Our quantum bit thread formulation may provide a way to investigate more fine-grained entanglement structures in general spacetimes., Comment: 32 pages, 4 figures; improvements to presentation; Figure 2 and Footnote 10 are added; published version in JHEP

We explore the generalized holographic complexity of odd-dimensional Myers-Perry asymptotically Anti-de Sitter (MP-AdS) black holes with equal angular momenta within the ``complexity equals anything'' proposal. We begin by determining the codimension-one generalized volume complexity by finding the extremum of the generally covariant volume functional. Locally, we show that its late-time growth rate aligns with the critical momenta associated with the extremal hypersurfaces. Globally, we discover diverse phase transitions for the complexity at early times, including first-order, second-order, and multi-critical transitions. An area law and a phase diagram are proposed to adapt to these phase behaviours, highlighting the effects of the black hole's angular momentum. At zero time, we define the generalized holographic complexity of formation and examine its scaling relations for both large near-extremal MP-AdS black holes and static charged black holes. We find that the scaling behaviours of the generalized volume complexity of formation maintain uniformity with those of the original holographic complexity formulations, except in cases where the scalar functional defining the generalized holographic complexity is infinite in the vacuum limit or at spatial infinity. Additionally, we show that these findings can be applied to codimension-zero observables., Comment: 38 pages, 15 figures

Quantum entanglement, crucial for understanding quantum many-body systems and quantum gravity, is commonly assessed through various measures such as von Neumann entropy, mutual information, and entanglement contour, each with its inherent limitations. In this work, we introduce the \textit{hyperfine structure of entanglement}, which dissects entanglement contours known as the fine structure into particle-number cumulants. This measure exhibits a set of universal properties with its significance in quantum information science. We apply it across diverse contexts: in Fermi gases, establishing connections to mutual information and interacting conformal field theory; in AdS$_3$/CFT$_2$ holographic duality, unveiling finer subregion-subregion duality and extending bulk reconstruction; and in Chern insulators, distinguishing between different quantum phases. Our findings suggest experimental accessibility, offering fresh insights into quantum entanglement across physical systems., Comment: title changed

In this paper, we investigate the topological numbers of the four-dimensional Schwarzschild black hole, $d$-dimensional Reissner-Nordstr\"om (RN) black hole, $d$-dimensional singly rotating Kerr black hole and five-dimensional Gauss-Bonnet black hole via the R\'enyi statistics. We find that the topological number calculated via the R\'enyi statistics is different from that obtained from the Gibbs-Boltzmann (GB) statistics. However, what is interesting is that the topological classifications of different black holes are consistent in both the R\'enyi and GB statistics: the four-dimensional RN black hole, four-dimensional and five-dimensional singly rotating Kerr black holes, five-dimensional charged and uncharged Gauss-Bonnet black holes belong to the same kind of topological class, and the four-dimensional Schwarzschild black hole and $d(>5)$-dimensional singly rotating Kerr black holes belong to another kind of topological class. In addition, our results suggest that the topological numbers calculated via the R\'enyi statistics in asymptotically flat spacetime background are equal to those calculated from the standard GB statistics in asymptotically AdS spacetime background, which provides more evidence for the connection between the nonextensivity of the R\'enyi parameter $\lambda$ and the cosmological constant $\Lambda$., Comment: 24 pages,19 figures

We study the information paradox of Reissner-Nordstr${\ddot{o}}$m anti-de Sitter (RN-AdS$_{d+1}$) black holes in the large dimension limit by using the island formula. The entanglement entropy of Hawking radiation is calculated both for the non-extremal and the extremal cases, in which the boundary of the radiation region is close to the outer horizon. For the non-extremal case, the entanglement entropy of Hawking radiation obeys the Page curve, i.e. the entanglement entropy of Hawking radiation increases with time and reaches saturation about twice Bekenstein-Hawking entropy at the Page time. For the extremal case, the entanglement entropy of Hawking radiation becomes ill-defined in the absence of the island due to the appearance of the singularity at the origin of the radial coordinate, while when the island exists, the entanglement entropy is found to be equal to the Bekenstein-Hawking entropy. In addition, for the case where the boundary of the radiation region is close to the horizon, there are some obvious constraints required by the existence of island solution for both non-extremal and extremal cases, which can be utilized to put constraints on the size of the black hole. These results reveal new features of the semi-classical large $d$ black holes from the island perspective., Comment: 25 pages, 7 figures

We reconsider $D\geq4$ dimensional asymptotically flat eternal Schwarzschild black hole, and focus on the situation where the inner boundary of the radiation region is chosen to be near the horizon (i.e. $\beta \ll1$). The tension between the near-horizon condition and the short-distance approximation emerges in large dimensions in $[JHEP 06 (2020) 085]$. We remove this tension by introducing a more proper near horizon condition, thus the resulting island solution is well-behaved in any $D\geq4$ dimensional spacetime. Interestingly, a novel constraint is obtained in this situation as required by the existence of the island solution, which directly leads to the constraints on the size of the Schwarzschild black hole, the position of the inner boundary for the radiation region, or the value of $c\cdot\tilde{G}_{N}$ in any $D\geq4$ dimension. When considering the large $D$ limit, the constraint on the size of the Schwarzschild black hole obtained in this situation is in agreement with the result given in $[Phys.Rev.D 102 (2020) 2, 026016]$. We interpret these as the unitary constraints implied by the presence of island in semiclassical gravity., Comment: 21 pages, 4 figures; improvements to the expression; Footnote 2 added to show a new analytical island solution for $n\rightarrow\infty$ while $\alpha\sim \beta/n$; accepted for publication in PRD

We study the partial entanglement entropy (PEE) aspects of the holographic BCFT setup with an entanglement island, inspired by the holographic triality of the AdS/BCFT setup developed in the recent study on the black hole information problem, and the "PEE=CFF (component flow flux)" prescription, which is proposed recently to investigate the holographic PEE in the framework of bit thread formulation. Our study provides a bit thread description of the AdS/BCFT setup, which characterizes the specific entanglement details between the different parts of the system with an entanglement island, and may provide further insight into the black hole information problem. Furthermore, we show that in the context of island, one should distinguish between the fine-grained PEE and the semi-classical PEE. Interestingly, similar to the island rule of the fine-grained entropy in the semi-classical picture, we also propose the island rules of the fine-grained PEE., Comment: 37 pages, 7 figures

In the holographic framework, we argue that the partial entanglement entropy (PEE) can be explicitly interpreted as the component flow flux in a locking bit thread configuration. By applying the locking theorem of bit threads, and constructing a concrete locking scheme, we obtain a set of uniquely determined component flow fluxes from this viewpoint, and successfully derive the PEE proposal and its generalized version in the multipartite cases. Moreover, from this perspective of bit threads, we also present a coherent explanation for the coincidence between the BPE (balanced partial entanglement)/EWCS (entanglement wedge cross section) duality proposed recently and the EoP (entanglement of purification)/EWCS duality. We also discuss the issues implied by this coincident between the idea of the PEE and the picture of locking thread configuration., Comment: 35 pages, 7 figures, accepted by jhep

We investigate the relations between bit thread, entanglement distillation and entanglement of purification in the holographic framework. Specifically, we give a bit thread interpretation for the one-shot entanglement distillation (OSED) tensor network, which can be understood as reconstructing the geometric structure of the bulk spacetime from the entanglement information of the boundary quantum system through the "surface growth scheme". Moreover, by showing that the holographic entanglement of purification (EoP) process can be regarded as a special case of our "surface growth scheme", we naturally obtain the bit thread interpretation of the holographic EoP in our framework, which turns out to be different from the existing interpretations. Since our interpretation for holographic EoP is obtained in a more general and physical framework, the advantage of our version is that it is more natural, and possibly more reasonable to reflect the real physical entanglement structures., Comment: 28 pages,10 figures

In a recent paper, a novel surface growth approach for reconstructing bulk geometry and matter fields was proposed, it was shown that this picture can be explicitly realized by the one-shot entanglement distillation tensor network and the surface state correspondence. In the present paper, we give direct analysis for the growth of the bulk minimal surfaces in asymptotically AdS 3 spacetime and show that bulk geometry can be efficiently reproduced in this way, which provides further support for the surface growth approach in entanglement wedge reconstruction.

We propose a surface growth approach to reconstruct the bulk spacetime geometry, motivated by Huygens'principle of wave propagation. We first construct a tensor network corresponding to a special surface growth picture with spherical symmetry and fractal feature using the one-shot entanglement distillation (OSED)method and show that the resulting tensor network is equivalent to the MERA-like tensor network, which gives a proof that the MERA-like tensor network is indeed a discretized version of the time slice of AdS spacetime, rather than just an analogy. Furthermore, we generalize the original OSED method to describe more general surface growth picture by using of surface/state correspondence and generalized RT formula, which leads to a more profound understanding for the surface growth process and provides a concrete and intuitive way for the idea of entanglement wedge reconstruction., Comment: 41 pages, 15 figures, accepted by JHEP

We study the Schwinger effect in near-extremal nonrotating black holes in an arbitrary $D(\geq 4)$-dimensional asymptotically flat and (A)dS space. Using the near-horizon geometry $\mathrm{AdS}_2 \times \mathrm{S}^{D-2}$ of near-extremal black holes with Myers-Perry metric, we find a universal expression of the emission formula for charges that is a multiplication of the Schwinger effects in an $\mathrm{AdS}_2$ space and in a two-dimensional Rindler space. The effective temperature of an accelerated charge for the Schwinger effect is determined by the radii of the effective $\mathrm{AdS}_2$ space and $\mathrm{S}^{D-2}$ as well as the mass, charge, angular momentum of the charge and the radius of the (A)dS space. The Schwinger effect in the asymptotically flat space is more efficient and persistent for a wide range of large black holes for dimensions higher than four. The AdS (dS) boundary enhances (suppresses) the Schwinger effect than the asymptotically flat space. The Schwinger effect persists for a wide range of black holes in the AdS space and has an upper bound in the dS space., Comment: RevTex 11 pages, 11 figures

We study the pair production of charged scalar particles from the five-dimensional near extremal Reissner- Nordstr\"om-Anti de Sitter (RN-AdS5) black hole. The pair production rate and the absorption cross section ratio in the full spacetime are obtained and are shown to have proportional relation with their counterparts in the near horizon region. In addition, the holographic descriptions of the pair production both in the IR CFT in the near horizon region and the UV CFT at the asymptotic spatial boundary of the RN-AdS5 black hole are analyzed in the AdS2/CFT1and AdS5/CFT4correspondences, respectively. This work gives a complete description of scalar pair production in the near extremal RN-AdS5black hole., Comment: 23pages, no figures

In the paper, based on recent studies on $T\bar{T}$ deformation of 2D field theory with supersymmetry, we investigate the deformed correlation functions in $\mathcal{N}=(1,1)$ and $\mathcal{N}=(2,2)$ 2D superconformal field theories. Up to the leading order in perturbation theory, we compute the correlation functions under $T\bar{T}$ deformation. The correlation functions in these undeformed theories are almost known, and together with the help of superconformal Ward identity in $\mathcal{N}=(1,1)$ and $\mathcal{N}=(2,2)$ theories respectively we can obtain the correlation functions with operator $T\bar{T}$ inserted. Finally, by employing dimensional regularization, we can work out the integrals in the first order perturbation. The study in this paper extends previous works on the correlation functions of $T\bar{T}$ deformed bosonic CFT to the supersymmetric case., Comment: 43 pages, published version

Tensor networks are powerful techniques that widely used in condensed matter physics. In this language, the wave function of a quantum manybody system is described by a network of tensors with specific entanglement structures. Recently, it is shown that tensor network can generate the anti-de Sitter (AdS) geometry by using the entanglement renormalization approach. However, whether the dynamical connections can be found between the tensor network and the gravity is an important unsolved problem. In this paper, we give a novel proposal to integrate ideas from tensor networks, entanglement entropy, canonical quantization of quantum gravity and the holographic principle and argue that the gravitational dynamics can be generated from a tensor network if the wave function of the latter satisfies the Wheeler-DeWitt equation., Comment: 10 pages

Using the symmetry of the near-horizon geometry and applying quantum field theory of a complex scalar field, we study the spontaneous pair production of charged scalars from near-extremal rotating, electrically and/or magnetically charged black holes. Analytical expressions for pair production, vacuum persistence and absorption cross section are found, and the spectral distribution is given a thermal interpretation. The pair production in near-extremal black holes has a factorization into the Schwinger effect in AdS and Schwinger effect in Rindler space, measuring the deviational from extremality. The associated holographical correspondence is confirmed at the 2-point function level by comparing the absorption cross section ratio as well as the pair production rate both from the gravity and the conformal field theories. The production of monopoles is discussed., Comment: 9 pages, contribution to the proceedings of 15th Marcel Grossmann Meeting (MG15)

In this paper we study the R\'{e}nyi entropy of 2D massless free fermions perturbed by the $T\bar{T}$ term and the $J\bar{T}$ term at the first order perturbation. Three cases, the vacuum state of infinite size system with $T\bar{T}$ perturbation, the excited states of finite size system with $T\bar{T}$ perturbation, and the vacuum state of infinite size system with $J\bar{T}$ perturbation, are analyzed. We use the bosonization approach to calculate the perturbative expansions of R\'{e}nyi entropy. In the bosonization language the twist operator is known explicitly, with which the computation of correlators in the perturbative expansion can be simply performed. Moreover, we show that the $T\bar{T}$ and $J\bar{T}$ terms have a simple form and are similar with each other. For the first and third cases, we reproduce the known results for R\'{e}nyi entropy using the bosonization method. While for the second case, we obtain new results for the excited states., Comment: 22 pages

In this paper, we study the acoustic black hole emerged from the nonextremal black D3-brane, based on the holographic approaches in constructing the acoustic black hole in asymptotically Anti de-Sitter spacetime (AAdS) and the effective hydrodynamic description of the nonextremal black D3-brane. We show that the holographic dual description of the acoustic black hole appeared on the timelike cutoff surface in the nonextremal black D3-brane also exist. The duality includes the dynamical connection between the acoustic black hole and the bulk gravity, a universal equation relating the Hawking-like temperature and the Hawking temperature, and a phonon/scalar channel quasinormal mode correspondence., Comment: 14 pages, no figures

We study the spontaneous pair production of scalar dyons in the near extremal dyonic Kerr-Newman (KN) black hole, which contains a warped AdS$_3$ structure in the near horizon region. The leading term contribution of the pair production rate and the absorption cross section ratio are also calculated using the Hamilton-Jacobi approach and the thermal interpretation is given. In addition, the holographic dual conformal field theories (CFTs) descriptions of the pair production rate and absorption cross section ratios are analyzed both in the $J$-, $Q$- and $P$-pictures respectively based on the threefold dyonic KN/CFTs dualities., Comment: 12 pages, 3 figures, revtex4. arXiv admin note: text overlap with arXiv:1607.02610

In the holographic description of cosmic preheating proposed in an accompanied Letter [1], the energy transfer between the inflaton and matter field at strong coupling is suggested to be mimicked by superfluid and normal components of a superconductor on Friedmann-Robertson-Walker (FRW) boundary in an asymptotically Anti-de Sitter (AdS) spacetime. In this paper we investigated two aspects of the scenario of holographic preheating that are not included in the accompanied work. Firstly, we study in detail the evolution of the quasi-normal modes (QNMs) surrounding a metastable hairy black hole. This analysis can quantitatively describe the preheating process of the matter field that is produced continuously in the case of strong coupling. Secondly, we present a detailed analysis of the holographic renormalization for the AdS-FRW background, which allows us to extract operator expectation values for studying cosmological implications., Comment: 8 pages, 2 figures, comments are most welcome

We propose a holographic description of cosmic preheating at strong coupling. In this scenario the energy transfer between the inflaton and matter field is mimicked by a model of holographic superconductor. An exponential amplification of the matter field during preheating can be described by the quasi-normal modes of a metastable "black hole" in the bulk spacetime with an expanding boundary. Our results reveal that the matter field can be produced continuously at strong coupling in contrast to the case of weak coupling with a discontinuous matter growth as inflaton oscillates. Furthermore, the amplification of matter field has an enhanced dependence on the vacuum expectation value of the inflaton at strong coupling. By virtue of the proposed mechanism, physics of the very early universe at an extremely high temperature right after inflation may become accessible., Comment: 5 pages, 2 figures, comments are most welcome

The spontaneous pair production of charged scalars in a near extremal Kerr-Newman (KN) black hole is analytically studied. It is shown that the existence condition for the pair production is equivalent to the violation of the Breitenlohner-Freedman bound in an AdS$_2$ space. The mean number of produced pairs in the extremal black hole has a thermal interpretation, in which the effective temperature for the Schwinger effect in the AdS$_2$ space persistently holds, while the mean number in the near extremal black hole has an additional factor of the Schwinger effect in the Rindler space. In addition, the holographic dual conformal field theory (CFT) descriptions of the charged scalar pair production are respectively realized both in the $J$ and $Q$ pictures in terms of the KN/CFTs correspondence., Comment: 13 pages, 3 figures, revtex4

We study the dual CFT description of the $d+1$-dimensional Reissner-Nordstr\"om-Anti de Sitter (RN-AdS$_{d+1}$) black hole in the large dimension (large $d$) limit, both for the extremal and nonextremal cases. The central charge of the dual CFT$_2$ (or chiral CFT$_1$) is calculated for the near horizon near extremal geometry which possess an AdS$_2$ structure. Besides, the $Q$-picture hidden conformal symmetry in the nonextremal background can be naturally obtained by a probe charged scalar field in the large $d$ limit, without the need to input the usual limits to probe the hidden conformal symmetry. Furthermore, an new dual CFT description of the nonextremal RN-AdS$_{d+1}$ black hole is found in the large $d$ limit and the duality is analyzed by comparing the entropies, the absorption cross sections and the retarded Green's functions obtained both from the gravity and the dual CFT sides., Comment: Latex, 18 pages, minor corrections and references added

We study the spontaneous pair production, including the Schwinger mechanism and the Hawking radiation, of charged scalar and spinor particles from the near horizon region of (near) extremal charged black holes in the probe field limit. The pair production rate and the absorption cross section, as well as the retarded Green's functions of the probe fields are analytically computed. Moreover, the holographic description dual to the pair production is discussed., Comment: 8 pages, 1 figure; contribution to the proceedings of 12th ICGAC (International Conference on Gravitation, Astrophysics and Cosmology), Moscow, June 28 - July 5, 2015

With the attempt to find the holographic description of usual acoustic black holes in fluid, we construct an acoustic black hole formed in the $d$-dimensional fluid located at the timelike cutoff surface of a neutral black brane in asymptotically AdS$_{d+1}$ spacetime, the bulk gravitational dual of the acoustic black hole is presented at first order of the hydrodynamic fluctuation. Moreover, the Hawking-like temperature of the acoustic black hole horizon is showed to be connected to the Hawking temperature of the real AdS black brane in the bulk, and the duality between the phonon scattering in the acoustic black hole and the sound channel quasinormal mode propagating in the bulk perturbed AdS black brane is extracted. We thus point out that, the acoustic black hole appeared in fluid, which was originally proposed as an analogous model to simulate Hawking radiation of the real black hole, is not merely an analogy, it can indeed be used to describe specific properties of the real AdS black holes, in the spirits of the fluid/gravity duality., Comment: 25 pages, no figures; title changed, minor changes, version to appear in PRD

The pair production of spinor particles, which can be captured by the solution of the Dirac equation with an appropriate boundary condition, in charged black holes is investigated. We obtain the closed form of the production rate in the near extremal limit of the Reissner-Nordstrom black holes. The cosmic censorship conjecture is seemingly guaranteed by the pair production process. Moreover, the absorption cross section ratio and retarded Green's functions of the spinor fields calculated from the gravity side match well with those of spinor operators in the dual CFT side., Comment: references added, errors corrected

We investigate the dynamical evolution of entanglement entropy in a holographic superconductor model by quenching the source term of the dual charged scalar operator. By access to the full background geometry, the holographic entanglement entropy is calculated for a strip geometry at the AdS boundary. It is found that the entanglement entropy exhibits a robust non-monotonic behaviour in time, independent of the strength of Gaussian quench and the size of the strip: it first displays a small dip, then grows linearly, and finally saturates. In particular, the linear growth velocity of the entanglement entropy has an upper bound for strip with large width; The equilibrium value of the non-local probe at late time shows a power law scaling behaviour with respect to the quench strength; Moreover, the entanglement entropy can uncover the dynamical transition at certain critical quench strength which happens to coincide with the one obtained form the dynamical evolution of scalar order parameter., Comment: 19 pages; 7 figures; compatible with JHEP version

We study the low-energy corrections to the holographic entanglement entropy (HEE) in the boundary CFT by perturbing the bulk geometry up to second order excitations. Focusing on the case that the boundary subsystem is a strip, we show that the area of the bulk minimal surface can be expanded in terms of the conserved charges, such as mass, angular momentum and electric charge of the AdS black brane. We also calculate the variation of the energy in the subsystem and verify the validity of the first law-like relation of thermodynamics at second order. Moreover, the HEE is naturally bounded at second order perturbations if the cosmic censorship conjecture for the dual black hole still holds., Comment: 25 pages, more discussions on validity of the 1st law-like relation at 2nd order added, references added

We study the optical conductivity in a (2+1)-dimensional non-relativistic field theory holographically dual to a (3+1)-dimensional charged Lifshitz black brane with the Einstein-Maxwell-dilaton theory. Surprisingly, we find that the optical AC conductivity satisfies the nontrivial (non-)power law scaling in the high frequency regime rather than approaching to a constant when the dynamical critical exponent $z>1$, which is qualitatively similar to those in various disordered solids in condensed matter systems. Besides, this (non-)power law scaling behavior shows some universality, which is robust against the temperatures. We argue that the peculiar scaling behavior of AC conductivity may stem from the couplings of the dilaton field with the gauge fields and also the logarithmic behavior near the boundary in the Lifshitz spacetime., Comment: 17 pages, 3 figures, 1 table, published version

We study the transport coefficients, including the conductivities and shear viscosity of the non-relativistic field theory dual to the Lifshitz black brane with multiple U(1) gauge fields by virtue of the gauge/gravity duality. Focusing on the case of double U(1) gauge fields, we systematically investigate the electric, thermal and thermoelectric conductivities for the dual non-relativistic field theory. In the large frequency regime, we find a nontrivial power law behavior in the electric AC conductivity when the dynamical critical exponent z>1 in (2+1)-dimensional field theory. The relations between this novel feature and the `symmetric hopping model' in condensed matter physics are discussed. In addition, we also show that the Kovtun-Starinets-Son bound for the shear viscosity to the entropy density is not violated by the additional U(1) gauge fields and dilaton in the Lifshitz black brane., Comment: 27 pages, 2 figures and 2 tables; References added and minor revisions made

We investigate the spontaneous pair production, including the Schwinger mechanism and the Hawking thermal radiation, of charged scalar particles from the near horizon region of a (near) extremal Reissner-Nordstr\"om black hole. The paradigm is equivalent to the dynamics of the charged scalar field in a specific AdS$_2 \times S^2$ spacetime with a constant electric field. Two possible boundary conditions are adopted to explicitly compute the corresponding production rate and absorption cross section. It is shown that the Schwinger production rate can be eventually suppressed by the increasing attractive gravitational force as the geometry changes from the extremal to the near extremal black hole. Consequently, the Schwinger mechanism and the Hawking radiation are generically indistinguishable for the near extremal black holes. The holographic description dual to the pair production is also briefly discussed., Comment: More comments and an appendix, including a figure, are added

In this article, we review recent studies on multiple dual 2D CFT descriptions of the Kerr-Newman black hole, in terms of the Kerr/CFT and Reissner-Nordstr\"om/CFT correspondences. A microscopic hair conjecture is suggested., Comment: 10 pages, contribution to the 2011 Shanghai Asia-Pacific School and Workshop on Gravitation

In this article we give a brief, nevertheless, comprehensive review on recent studies in the quantum gravity description of the Reissner-Nordstr\"om (RN) black hole from the perspective of the AdS/CFT correspondence. We survey the known evidence supporting a two-dimensional conformal field theory (CFT) description holographically dual to the RN black hole., Comment: 10 pages, contribution to the proceedings of IARD 2010 conference, to appear in Journal of Physics: Conference Series

In this paper, we suggest that there are two different individual 2D CFTs holographically dual to the Kerr-Newman black hole, coming from the corresponding two possible limits --- the Kerr/CFT and Reissner-Nordstr\"om/CFT correspondences, namely there exist the Kerr-Newman/CFTs dualities. A probe scalar field at low frequencies turns out can exhibit two different 2D conformal symmetries (named by $J$- and $Q$-pictures, respectively) in its equation of motion when the associated parameters are suitably specified. These twofold dualities are supported by the matchings of entropies, absorption cross sections and real time correlators computed from both the gravity and the CFT sides. Our results lead to a fascinating "microscopic no hair conjecture" --- for each macroscopic hair parameter, in additional to the mass of a black hole in the Einstein-Maxwell theory, there should exist an associated holographic CFT$_2$ description., Comment: 21 pages, 1 figure, typos corrected

It is shown that the hidden conformal symmetry, namely $SO(2,2) \sim SL(2,R)_L \times SL(2,R)_R$ symmetry, of the non-extremal dyonic Reissner-Nordstr\"om black hole can be probed by a charged massless scalar field at low frequencies. The existence of such hidden conformal symmetry suggests that the field theory holographically dual to the 4D Reissner-Nordstr\"om black hole indeed should be a 2D CFT. Although the associated AdS$_3$ structure does not explicitly appear in the near horizon geometry, the primary parameters of the dual CFT$_2$ can be exactly obtained without the necessity of embedding the 4D Reissner-Nordstr\"om black hole into 5D spacetime. The duality is further supported by comparing the absorption cross sections and real-time correlators obtained from both the CFT and the gravity sides., Comment: 18 pages, no figure, typos corrected

Motivated by recent progresses in the holographic descriptions of the Kerr and Reissner-Nordstr{\o}m (RN) black holes, we explore the hidden conformal symmetry of nonextremal uplifted 5D RN black hole by studying the near horizon wave equation of a massless scalar field propagating in this background. Similar to the Kerr black hole case, this hidden symmetry is broken by the periodicity of the associated angle coordinate in the background geometry, but the results somehow testify the dual CFT description of the nonextremal RN black holes. The duality is further supported by matching of the entropies and absorption cross sections calculated from both CFT and gravity sides., Comment: 14 pages, no figure

We reconsidered the quantum gravity description of the near horizon extremal Reissner-Nordstr{\o}m black hole in the viewpoint of the AdS$_2$/CFT$_1$ correspondence. We found that, for pure electric case, the right moving central charge of dual 1D CFT is $6 Q^2$ which is different from the previous result $6 Q^3$ of left moving sector obtained by warped AdS$_3$/CFT$_2$ description. We discussed the discrepancy in these two approaches and examined novel properties of our result., Comment: revtex4, 16 pages, sign mistakes corrected, references included

From the perspective of AdS/CFT correspondence, we study the gravitational Chern-Simons term correction to the holographic entanglement entropy of CFT on the conformal boundary of asymptotically AdS$_3$ spacetime using the off-shell Euclidean path integral method. We show that, like the BTZ black hole entropy, the holographic entanglement entropy is indeed modified due to the gravitational Chern-Simons term although the bulk geometry does not change., Comment: 20 pages, minor corrections made, comments added

We apply Wilczek and his collaborators' anomaly cancellation approach to the 3-dimensional Schwarzschild- and BTZ-like brane world black holes induced by the generalized C metrics in the Randall-Sundrum scenario. Based on the fact that the horizon of brane world black hole will extend into the bulk spacetime, we do the calculation from the bulk generalized C metrics side and show that this approach also reproduces the correct Hawking radiation for these brane world black holes. Besides, since this approach does not involve the dynamical equation, it also shows that the Hawking radiation is only a kinematic effect., Comment: 11 pages. v2: minor changes and references added