# Quantum Gravity & Holography Domain: Fundamental & Quantum Physics · 248 papers indexed · newest 2026-10-29 AdS/CFT, the black-hole information problem and islands, entanglement and the emergence of spacetime, and de Sitter quantum gravity. Key concepts: AdS/CFT, holography, black hole information, Page curve, entanglement island, quantum gravity, de Sitter ## Research dossier (premium) **Quantum Gravity & Holography: State of the Field (October 2026)** (v1, updated 2026-10-30; 4,262 words, 54 sources, 30 evidence-mapped claims) This dossier surveys holography and quantum gravity as of October 2026: AdS/CFT and its dictionary, entanglement islands and the Page curve, de Sitter holography, tensor-network models and holographic constraints on symmetry. The most important takeaway is that island calculations yield unitary Page curves in many AdS settings, while braneworld results depend on the brane gravity and de Sitter analogues remain contested and unconfirmed. - Preview (free): https://space-kitty.com/api/v1/dossiers/quantum-gravity-holography/preview - Full dossier ($0.20 via x402): https://space-kitty.com/api/v1/dossiers/quantum-gravity-holography - Research pack ($0.20): https://space-kitty.com/api/v1/topics/quantum-gravity-holography/pack ## Most influential - **[Non-Fermi liquids from holography](https://space-kitty.com/papers/arxiv:0903.2477)**. Hong Liu, John McGreevy, David Vegh · 2011 · Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields (arXiv:0903.2477 · doi:10.1103/physrevd.83.065029 · 487 citations). Source: > We report on a potentially new class of non-Fermi liquids in (2+1)-dimensions. They are identified via the response functions of composite fermionic operators in a class of strongly interacting quantum field theories at finite density, computed using the AdS/CFT correspondence. We find strong evidence of Fermi surfaces: gapless fermionic excitations at discrete shells in momentum space. The spectral weight exhibits novel phenomena, including particle-hole asymmetry, discrete scale invariance, and scaling behavior consistent with that of a critical Fermi surface postulated by Senthil. - **[Entanglement of purification: from spin chains to holography](https://space-kitty.com/papers/arxiv:1709.07424)**. Phuc Nguyen, Trithep Devakul, Matthew G. Halbasch et al. · 2018 · Journal of High Energy Physics (arXiv:1709.07424 · doi:10.1007/jhep01(2018)098 · 240 citations). Source: > Purification is a powerful technique in quantum physics whereby a mixed quantum state is extended to a pure state on a larger system. This process is not unique, and in systems composed of many degrees of freedom, one natural purification is the one with minimal entanglement. Here we study the entropy of the minimally entangled purification, called the entanglement of purification, in three model systems: an Ising spin chain, conformal field theories holographically dual to Einstein gravity, and random stabilizer tensor networks. We conjecture values for the entanglement of purification in all… - **[An Information Paradox and Its Resolution in de Sitter Holography](https://space-kitty.com/papers/arxiv:2103.07477)**. Hao Geng, Yasunori Nomura, Hao-Yu Sun · 2021 · Phys. Rev. D 103, 126004 (2021) (arXiv:2103.07477 · doi:10.1103/physrevd.103.126004 · 144 citations). Source: > We formulate a version of the information paradox in de Sitter spacetime and show that it is solved by the emergence of entanglement islands in the context of the DS/dS correspondence; in particular, the entanglement entropy of a subregion obeys a time-dependent Page curve. Our construction works in general spacetime dimensions and keeps the graviton massless. We interpret the resulting behavior of the entanglement entropy using double holography. It suggests that the spatial distribution of microscopic degrees of freedom depends on descriptions, as in the case of a black hole. In the static (… - **[Surface/state correspondence as a generalized holography](https://space-kitty.com/papers/arxiv:1503.03542)**. Masamichi Miyaji, Tadashi Takayanagi · 2015 · Progress of Theoretical and Experimental Physics (arXiv:1503.03542 · doi:10.1093/ptep/ptv089 · 184 citations). Source: > We propose a new duality relation between codimension two space-like surfaces in gravitational theories and quantum states in dual Hilbert spaces. This surface/state correspondence largely generalizes the idea of holography such that we do not need to rely on any existence of boundaries in gravitational spacetimes. The present idea is motivated by the recent interpretation of AdS/CFT in terms of the tensor networks so called MERA. Moreover, we study this correspondence from the viewpoint of entanglement entropy and information metric. The Cramer-Rao bound in quantum estimation theory implies t… - **[The Black Hole Information Problem](https://space-kitty.com/papers/arxiv:1609.04036)**. Joseph Polchinski · 2016 (arXiv:1609.04036 · doi:10.1142/9789813149441_0006 · 147 citations). Source: > The black hole information problem has been a challenge since Hawking's original 1975 paper. It led to the discovery of AdS/CFT, which gave a partial resolution of the paradox. However, recent developments, in particular the firewall puzzle, show that there is much that we do not understand. I review the black hole, Hawking radiation, and the Page curve, and the classic form of the paradox. I discuss AdS/CFT as a partial resolution. I then discuss black hole complementarity and its limitations, leading to many proposals for different kinds of \`drama.' I conclude with some recent ideas. - **[Global symmetry, Euclidean gravity, and the black hole information problem](https://space-kitty.com/papers/arxiv:2010.10539)**. Daniel Harlow, Edgar Shaghoulian · 2020 · Journal of High Energy Physics (arXiv:2010.10539 · doi:10.1007/jhep04(2021)175 · 95 citations). Source: > In this paper we argue for a close connection between the non-existence of global symmetries in quantum gravity and a unitary resolution of the black hole information problem. In particular we show how the essential ingredients of recent calculations of the Page curve of an evaporating black hole can be used to generalize a recent argument against global symmetries beyond the AdS/CFT correspondence to more realistic theories of quantum gravity. We also give several low-dimensional examples of quantum gravity theories which do not have a unitary resolution of the black hole information problem … - **[Mass, Entropy and Holography in Asymptotically de Sitter Spaces](https://space-kitty.com/papers/arxiv:hep-th/0110108)**. Vijay Balasubramanian, Jan de Boer, Djordje Minic · 2001 · Phys.Rev. D65 (2002) 123508 (arXiv:hep-th/0110108 · doi:10.1103/physrevd.65.123508 · 409 citations). Source: > We propose a novel prescription for computing the boundary stress tensor and charges of asymptotically de Sitter (dS) spacetimes from data at early or late time infinity. If there is a holographic dual to dS spaces, defined analogously to the AdS/CFT correspondence, our methods compute the (Euclidean) stress tensor of the dual. We compute the masses of Schwarzschild-de Sitter black holes in four and five dimensions, and the masses and angular momenta of Kerr-de Sitter spaces in three dimensions. All these spaces are less massive than de Sitter, a fact which we use to qualitatively and quantita… - **[BCFT and Islands in two dimensions](https://space-kitty.com/papers/arxiv:2202.08462)**. Kenta Suzuki, Tadashi Takayanagi · 2022 · Journal of High Energy Physics (arXiv:2202.08462 · doi:10.1007/jhep06(2022)095 · 83 citations). Source: > By combining the AdS/BCFT correspondence and the brane world holography, we expect an equivalence relation between a boundary conformal field theory (BCFT) and a gravitational system coupled to a CFT. However, it still remains unclear how the boundary condition of the BCFT is translated in the gravitational system. We examine this duality relation in a two-dimensional setup by looking at the computation of entanglement entropy and energy flux conservation. We also identify the two-dimensional gravity which is dual to the boundary dynamics of a BCFT. Moreover, we show that by considering a grav… - **[Localization & exact holography](https://space-kitty.com/papers/doi:10.1007/jhep04(2013)062)**. Atish Dabholkar A, João Gomes, Sameer Murthy · 2013 · Journal of High Energy Physics (doi:10.1007/jhep04(2013)062 · 103 citations). Source: > A bstract We consider the AdS 2 /CFT 1 holographic correspondence near the horizon of big four-dimensional black holes preserving four supersymmetries in toroidally compactified Type-II string theory. The boundary partition function of CFT 1 is given by the known quantum degeneracies of these black holes. The bulk partition function is given by a functional integral over string fields in AdS 2 . Using recent results on localization we reduce the infinite-dimensional functional integral to a finite number of ordinary integrals over a space of localizing instantons. Under reasonable assumptions … > _Abstract excerpt by Atish Dabholkar A et al., CC-BY, https://doi.org/10.1007/jhep04(2013)062; truncated._ - **[Conceptual Aspects of Gauge/Gravity Duality](https://space-kitty.com/papers/arxiv:1509.09231)**. Sebastian De Haro, Daniel R. Mayerson, Jeremy Butterfield · 2016 · Foundations of Physics (arXiv:1509.09231 · doi:10.1007/s10701-016-0037-4 · 90 citations). Source: > We give an introductory review of gauge/gravity duality, and associated ideas of holography, emphasising the conceptual aspects. The opening Sections gather the ingredients, viz. anti-de Sitter spacetime, conformal field theory and string theory, that we need for presenting, in Section 5, the central and original example: Maldacena's AdS/CFT correspondence. Sections 6 and 7 develop the ideas of this example, also in applications to condensed matter systems, QCD, and hydrodynamics. Sections 8 and 9 discuss the possible extensions of holographic ideas to de Sitter spacetime and to black holes. S… - **[Black hole elasticity and gapped transverse phonons in holography](https://space-kitty.com/papers/arxiv:1708.08477)**. Lāsma Alberte, Martin Ammon, Matteo Baggioli et al. · 2018 · Journal of High Energy Physics (arXiv:1708.08477 · doi:10.1007/jhep01(2018)129 · 87 citations). Source: > We study the elastic response of planar black hole (BH) solutions in a simple class of holographic models with broken translational invariance. We compute the transverse quasi-normal mode spectrum and the propagation speed of the lowest energy mode. We find that the speed of the lowest mode relates to the BH rigidity modulus as dictated by elasticity theory. This allows to identify these modes as transverse phonons---the pseudo Goldstone bosons of spontaneously broken translational invariance. In addition, we show that these modes have a mass gap controlled by an explicit source of the transla… - **[Entanglement Island and Page Curve in Wedge Holography](https://space-kitty.com/papers/arxiv:2301.06285)**. Rong-Xin Miao · 2023 · JHEP03(2023)214 (arXiv:2301.06285 · doi:10.1007/jhep03(2023)214 · 33 citations). Source: > Entanglement islands play an essential role in the recent breakthrough in resolving the black hole information paradox. However, whether entanglement islands can exist in massless gravity theories is controversial. It is found that entanglement islands disappear in the initial model of wedge holography with massless gravity on the brane. As a result, the entanglement entropy of Hawking radiation becomes a time-independent constant, and there is no Page curve. In this paper, we recover massless entanglement islands in wedge holography with suitable DGP gravity or higher derivative gravity on th… - **[Gravitational quasinormal modes for Anti-de Sitter black holes](https://space-kitty.com/papers/arxiv:gr-qc/0201016)**. Ian G Moss, James P Norman · 2002 · Class.Quant.Grav. 19 (2002) 2323-2332 (arXiv:gr-qc/0201016 · doi:10.1088/0264-9381/19/8/319 · 157 citations). Source: > Quasinormal mode spectra for gravitational perturbations of black holes in four dimensional de Sitter and anti-de Sitter space are investigated. The anti-de Sitter case is relevant to the ADS-CFT correspondence in superstring theory. The ADS-CFT correspondence suggests a prefered set of boundary conditions. - **[Massless Entanglement Islands in Cone Holography](https://space-kitty.com/papers/arxiv:2303.10958)**. Dongqi Li, Rong-Xin Miao · 2023 · JHEP06(2023)056 (arXiv:2303.10958 · doi:10.1007/jhep06(2023)056 · 30 citations). Source: > It is controversial whether entanglement islands can exist in massless gravity theories. Recently, it is found that the massless entanglement island appears in wedge holography with DGP gravity on the branes. In this paper, we generalize the discussions to the codim-n holography named cone holography. For simplicity, we focus on the case with a codim-2 E brane and a codim-1 Q brane. We discuss the effective action, mass spectrum and holographic entanglement entropy for cone holography with DGP terms. We verify that there is massless gravity on the branes, and recover non-trivial entanglement i… - **[A Half de Sitter Holography](https://space-kitty.com/papers/arxiv:2306.07575)**. Taishi Kawamoto, Shan-Ming Ruan, Yu-ki Suzuki et al. · 2023 · Journal of High Energy Physics (arXiv:2306.07575 · doi:10.1007/jhep10(2023)137 · 33 citations). Source: > A long-standing and intriguing question is: does the holographic principle apply to cosmologies like de Sitter spacetime? In this work, we consider a half dS spacetime wherein a timelike boundary encloses the bulk spacetime, presenting a version of de Sitter holography. By analyzing the holographic entanglement entropy in this space and comparing it with that in AdS/CFT, we argue that gravity on a half dS$\_{d+1}$ is dual to a highly non-local field theory residing on dS$\_d$ boundary. This non-locality induces a breach in the subadditivity of holographic entanglement entropy. Remarkably, this o… ## Newest - **[Photon Rings and Mass-Independent Observables of a Five-Dimensional Charged AdS Black Hole](https://space-kitty.com/papers/arxiv:2610.40069)**. Amrillokhon Mamatkhonov, Javokhir Sharipov, Tursunali Xamidov et al. · 2026 (arXiv:2610.40069). Source: - **[Twinor Theory: Field Equations from $(A)dS\_4^{\\mathbb C}$ Spin-Tractors: A Twin to Twistor Theory Modelled on $(A)dS\_4^{\\mathbb C}$](https://space-kitty.com/papers/arxiv:2610.40435)**. Chen-Hsu Chien · 2026 (arXiv:2610.40435). Source: - **[On Geometric Observables in Gravity](https://space-kitty.com/papers/arxiv:2610.40615)**. Manthos Karydas, Murat Kologlu, Allic Sivaramakrishnan · 2026 (arXiv:2610.40615). Source: - **[Holography and localization in fractional field theory](https://space-kitty.com/papers/arxiv:2610.38806)**. Gianluca Calcagni, Iván Salvador-García · 2026 (arXiv:2610.38806). Source: - **[Gravitational Reconstruction in $AdS\_{4}$](https://space-kitty.com/papers/arxiv:2610.38887)**. David A. Lowe, Yiru Wang, Juanyi Yang · 2026 (arXiv:2610.38887). Source: - **[Are Black Hole and Cosmological Horizon Thermodynamics Necessarily Inequivalent?](https://space-kitty.com/papers/arxiv:2610.39048)**. Zachary J. Hoelscher · 2026 (arXiv:2610.39048). Source: - **[Testing Conformal Weyl Gravity with Plasma Modified Black Hole Shadows and EHT Constraints](https://space-kitty.com/papers/arxiv:2610.36562)**. Zhichen Guan, Connor McMillin, Owen Gartlan et al. · 2026 (arXiv:2610.36562). Source: - **[The Disordered Universe 2025: Statistical Systems Out of Equilibrium](https://space-kitty.com/papers/arxiv:2610.36997)**. Weam Abou Hamdan, Martí Berenguer Mimó, Rafael Carrasco Carmona et al. · 2026 (arXiv:2610.36997). Source: - **[Can One Hear the Absence of a Singularity?](https://space-kitty.com/papers/arxiv:2610.37028)**. Matteo Della Rocca, Paolo Pani, Andrea P. Sanna · 2026 (arXiv:2610.37028). Source: - **[The Disordered Universe 2025: Features in a $Λ\>0$ Universe](https://space-kitty.com/papers/arxiv:2610.37117)**. Samuel Brian, Yakov Landau, Tommaso Marini et al. · 2026 (arXiv:2610.37117). Source: --- Space Kitty Archive · https://space-kitty.com · API: https://space-kitty.com/api/v1 · MCP: https://space-kitty.com/mcp · Premium: $0.20/request via x402 (Base Sepolia (testnet)). Metadata: arXiv (CC0), OpenAlex (CC0), Europe PMC (CC BY/CC0 works), ClinicalTrials.gov.