Entanglement wedge reconstruction using the Petz map
Open accessAbstract
Abstract At the heart of recent progress in AdS/CFT is the question of subregion duality, or entanglement wedge reconstruction: which part(s) of the boundary CFT are dual to a given subregion of the bulk? This question can be answered by appealing to the quantum error correcting properties of holography, and it was recently shown that robust bulk (entanglement wedge) reconstruction can be achieved using a universal recovery channel known as the twirled Petz map. In short, one can use the twirled Petz map to recover bulk data from a subset of the boundary. However, this map involves an averaging procedure over bulk and boundary modular time, and hence it can be somewhat intractable to evaluate in practice. We show that a much simpler channel, the Petz map, is sufficient for entanglement wedge reconstruction for any code space of fixed finite dimension — no twirling is required. Moreover, the error in the reconstruction will always be non-perturbatively small. From a quantum information perspective, we prove a general theorem extending the use of the Petz map as a general-purpose recovery channel to subsystem and operator algebra quantum error correction.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
Let M_a be a subalgebra on the code space C with dimension d_code, and N be any noise map. Suppose there exists an optimal recovery map R_opt such that (R_opt • N)(ρ) - ρ_a < δ for all ρ ∈ B(C) and its projection ρ_a onto M_a. Then the Petz map R_τ,N defined using the maximally mixed state τ on the codespace satisfies (R_τ,N • N)(ρ)|_a - ρ_a ≤ d_code √(8δ).
“Let M a be a subalgebra on the code space C with dimension d code , and N be any noise map.Suppose there exists an optimal recovery map R opt such that (R opt • N )(ρ) -ρ a 1 < δ, for all ρ ∈ B(C) and its projection ρ a onto M a .Then, the Petz map R τ,N (.) ≡ 1 d code N † N (τ ) -1/2 (.)N (τ ) -1/2 , defined using the maximally mixed state τ on the codespace, satisfies, (R τ,N ) • N )(ρ)| a -ρ a”
From Holographic spacetime, black holes and quantum error correcting codes: a review (2022) · cites this paper as [187]
The standard form of the Petz map in Eq. (68) suffices to achieve approximate bulk reconstruction.
“Moving away from the twirled Petz map which involves an averaging over the modular time, it was argued in [187] that the standard form of the Petz map in Eq. ( 68) suffices to achieve approximate bulk reconstruction.”
From Holographic spacetime, black holes and quantum error correcting codes: a review (2022) · cites this paper as [187]
Cites
Ryu, S., & Takayanagi, T. (2006) · Physical Review Letters · doi:10.1103/physrevlett.96.181602 · Cited by 4,302 · see citing works
A covariant holographic entanglement entropy proposal
Hubeny, V. E., Rangamani, M., & Takayanagi, T. (2007) · Journal of High Energy Physics · doi:10.1088/1126-6708/2007/07/062 · Cited by 1,822 · see citing works
A Covariant Holographic Entanglement Entropy Proposal
Hubeny, V. E., Rangamani, M., & Takayanagi, T. (2007) · arXiv · doi:10.48550/arxiv.0705.0016 · Cited by 1,822
The large N limit of superconformal field theories and supergravity
MALDACENA, J. M. (1999) · AIP conference proceedings · doi:10.1063/1.59653 · Cited by 1,624 · see citing works
Generalized gravitational entropy
Lewkowycz, A., & Maldacena, J. (2013) · Journal of High Energy Physics · doi:10.1007/jhep08(2013)090 · Cited by 1,183 · see citing works
Holographic quantum error-correcting codes: toy models for the bulk/boundary correspondence
Pastawski, F., Yoshida, B., Harlow, D., & Preskill, J. (2015) · Journal of High Energy Physics · doi:10.1007/jhep06(2015)149 · Cited by 958 · see citing works
Quantum corrections to holographic entanglement entropy
Faulkner, T., Lewkowycz, A., & Maldacena, J. (2013) · Journal of High Energy Physics · doi:10.1007/jhep11(2013)074 · Cited by 945 · see citing works
Quantum extremal surfaces: holographic entanglement entropy beyond the classical regime
Engelhardt, N., & Wall, A. C. (2015) · Journal of High Energy Physics · doi:10.1007/jhep01(2015)073 · Cited by 836 · see citing works
Bulk locality and quantum error correction in AdS/CFT
Almheiri, A., Dong, X., & Harlow, D. (2015) · Journal of High Energy Physics · doi:10.1007/jhep04(2015)163 · Cited by 802 · see citing works
Cryptographic distinguishability measures for quantum-mechanical states
Fuchs, C. A., & van de Graaf, J. (1999) · IEEE Transactions on Information Theory · doi:10.1109/18.761271 · Cited by 759 · see citing works
Maximin surfaces, and the strong subadditivity of the covariant holographic entanglement entropy
Wall, A. C. (2014) · Classical and Quantum Gravity · doi:10.1088/0264-9381/31/22/225007 · Cited by 545 · see citing works
Reconstruction of Bulk Operators within the Entanglement Wedge in Gauge-Gravity Duality
Dong, X., Harlow, D., & Wall, A. C. (2016) · Physical Review Letters · doi:10.1103/physrevlett.117.021601 · Cited by 541 · see citing works
Relative entropy equals bulk relative entropy
Jafferis, D. L., Lewkowycz, A., Maldacena, J., & Suh, S. J. (2016) · Journal of High Energy Physics · doi:10.1007/jhep06(2016)004 · Cited by 539 · see citing works
Relative entropy equals bulk relative entropy
Jafferis, D. L., Lewkowycz, A., Maldacena, J., & Suh, S. J. (2015) · arXiv · doi:10.48550/arxiv.1512.06431 · Cited by 534
The gravity dual of a density matrix
Czech, B., Karczmarek, J. L., Nogueira, F., & Van Raamsdonk, M. (2012) · Classical and Quantum Gravity · doi:10.1088/0264-9381/29/15/155009 · Cited by 428 · see citing works
Causality & holographic entanglement entropy
Headrick, M., Hubeny, V. E., Lawrence, A., & Rangamani, M. (2014) · Journal of High Energy Physics · doi:10.1007/jhep12(2014)162 · Cited by 418 · see citing works
The Ryu–Takayanagi Formula from Quantum Error Correction
Harlow, D. (2017) · Communications in Mathematical Physics · doi:10.1007/s00220-017-2904-z · Cited by 384 · see citing works
Reversing quantum dynamics with near-optimal quantum and classical fidelity
Barnum, H., & Knill, E. (2002) · Journal of Mathematical Physics · doi:10.1063/1.1459754 · Cited by 280 · see citing works
Entanglement Wedge Reconstruction via Universal Recovery Channels
Cotler, J., Hayden, P., Penington, G., Salton, G., Swingle, B., & Walter, M. (2017) · arXiv · doi:10.48550/arxiv.1704.05839 · Cited by 221
Self-citationEntanglement Wedge Reconstruction via Universal Recovery Channels
Cotler, J., Hayden, P., Penington, G., Salton, G., Swingle, B., & Walter, M. (2019) · Physical Review X · doi:10.1103/physrevx.9.031011 · Cited by 221 · see citing works
Self-citationBulk locality from modular flow
Faulkner, T., & Lewkowycz, A. (2017) · Journal of High Energy Physics · doi:10.1007/jhep07(2017)151 · Cited by 217 · see citing works
Entropy, extremality, euclidean variations, and the equations of motion
Dong, X., & Lewkowycz, A. (2018) · Journal of High Energy Physics · doi:10.1007/jhep01(2018)081 · Cited by 135 · see citing works
Entropy, Extremality, Euclidean Variations, and the Equations of Motion
Dong, X., & Lewkowycz, A. (2017) · arXiv · doi:10.48550/arxiv.1705.08453 · Cited by 135
Learning the Alpha-bits of black holes
Hayden, P., & Penington, G. (2019) · Journal of High Energy Physics · doi:10.1007/jhep12(2019)007 · Cited by 125 · see citing works
Self-citationUniversal Recovery Maps and Approximate Sufficiency of Quantum Relative Entropy
Junge, M., Renner, R., Sutter, D., Wilde, M. M., & Winter, A. (2018) · Annales Henri Poincaré · doi:10.1007/s00023-018-0716-0 · Cited by 118 · see citing works
Boundary-to-bulk maps for AdS causal wedges and the Reeh-Schlieder property in holography
Morrison, I. A. (2014) · Journal of High Energy Physics · doi:10.1007/jhep05(2014)053 · Cited by 111 · see citing works
Squashed Entanglement, $$\mathbf {k}$$ k -Extendibility, Quantum Markov Chains, and Recovery Maps
Li, K., & Winter, A. (2018) · Foundations of Physics · doi:10.1007/s10701-018-0143-6 · Cited by 71 · see citing works
Local bulk operators in AdS/CFT and the fate of the BTZ singularity
Sharpe, E., & Greenspoon, A. (2008) · AMS/IP studies in advanced mathematics · doi:10.1090/amsip/044/07 · Cited by 34 · see citing works
Work and reversibility in quantum thermodynamics
Alhambra, A. M., Wehner, S., Wilde, M. M., & Woods, M. P. (2018) · Physical Review A · doi:10.1103/physreva.97.062114 · Cited by 27 · see citing works
Dynamical maps, quantum detailed balance, and the Petz recovery map
Alhambra, A. M., & Woods, M. P. (2017) · Physical Review A · doi:10.1103/physreva.96.022118 · Cited by 25 · see citing works
Information-theoretic limitations on approximate quantum cloning and broadcasting
Lemm, M., & Wilde, M. M. (2017) · Physical Review A · doi:10.1103/physreva.96.012304 · Cited by 19 · see citing works
Flagged first, then by citations
Cited by
Sorted by citations
Entanglement wedge reconstruction and the information paradox
Penington, G. (2020) · Journal of High Energy Physics · doi:10.1007/jhep09(2020)002 · Cited by 968 · see citing works
Self-citationReplica wormholes and the black hole interior
Penington, G., Shenker, S. H., Stanford, D., & Yang, Z. (2019) · arXiv · doi:10.48550/arxiv.1911.11977 · Cited by 809
Self-citationReplica wormholes and the black hole interior
Penington, G., Shenker, S. H., Stanford, D., & Yang, Z. (2022) · Journal of High Energy Physics · doi:10.1007/jhep03(2022)205 · Cited by 807 · see citing works
“We show this directly by using gravitational path integrals to evaluate matrix elements of an explicit reconstruction operator defined using the Petz map [41, 42] (see [39, 43] for a description and recent discussion of the Petz map).”
MethodSelf-citationPulling out the island with modular flow
Chen, Y. (2020) · Journal of High Energy Physics · doi:10.1007/jhep03(2020)033 · Cited by 88 · see citing works
Leading order corrections to the quantum extremal surface prescription
Akers, C., & Penington, G. (2021) · Journal of High Energy Physics · doi:10.1007/jhep04(2021)062 · Cited by 98 · see citing works
Self-citationEffective entropy of quantum fields coupled with gravity
Dong, X., Qi, X.-L., Shangnan, Z., & Yang, Z. (2020) · Journal of High Energy Physics · doi:10.1007/jhep10(2020)052 · Cited by 78 · see citing works
Cauchy slice holography: a new AdS/CFT dictionary
Araujo-Regado, G., Khan, R., & Wall, A. C. (2023) · Journal of High Energy Physics · doi:10.1007/jhep03(2023)026 · Cited by 94 · see citing works
From Time-Reversal Symmetry to Quantum Bayes’ Rules
Parzygnat, A. J., & Fullwood, J. (2023) · PRX Quantum · doi:10.1103/prxquantum.4.020334 · Cited by 51 · see citing works
Quantum Gravity in the Lab. II. Teleportation by Size and Traversable Wormholes
Nezami, S., Lin, H. W., Brown, A. R., Gharibyan, H., Leichenauer, S., Salton, G., Susskind, L., Swingle, B. G., & Walter, M. (2023) · PRX Quantum · doi:10.1103/prxquantum.4.010321 · Cited by 50 · see citing works
Self-citationThe Page curve for reflected entropy
Akers, C., Faulkner, T., Lin, S., & Rath, P. (2022) · Journal of High Energy Physics · doi:10.1007/jhep06(2022)089 · Cited by 51 · see citing works
Holographic spacetime, black holes and quantum error correcting codes: a review
Kibe, T., Mandayam, P., & Mukhopadhyay, A. (2022) · The European Physical Journal C · doi:10.1140/epjc/s10052-022-10382-1 · Cited by 44 · see citing works
Island for gravitationally prepared state and pseudo entanglement wedge
Miyaji, M. (2021) · Journal of High Energy Physics · doi:10.1007/jhep12(2021)013 · Cited by 45 · see citing works
Causal structures and nonlocality in double holography
Omiya, H., & Wei, Z. (2022) · Journal of High Energy Physics · doi:10.1007/jhep07(2022)128 · Cited by 45 · see citing works
Cosmology from random entanglement
Antonini, S., Sasieta, M., & Swingle, B. G. (2023) · Journal of High Energy Physics · doi:10.1007/jhep11(2023)188 · Cited by 39 · see citing works
Balanced partial entanglement and mixed state correlations
Camargo, H. A., Nandy, P., Wen, Q., & Zhong, H. (2022) · SciPost Physics · doi:10.21468/scipostphys.12.4.137 · Cited by 38 · see citing works
Headrick, M., & Hubeny, V. E. (2023) · Journal of High Energy Physics · doi:10.1007/jhep07(2023)180 · Cited by 38 · see citing works
Axioms for retrodiction: achieving time-reversal symmetry with a prior
Parzygnat, A. J., & Buscemi, F. (2023) · Quantum · doi:10.22331/q-2023-05-23-1013 · Cited by 33 · see citing works
Islands and mixed states in closed universes
Fallows, S., & Ross, S. F. (2021) · Journal of High Energy Physics · doi:10.1007/jhep07(2021)022 · Cited by 31 · see citing works
Gravity dual of Connes cocycle flow
Raphael Bousso, A., Chandrasekaran, V., Rath, P., & Shahbazi-Moghaddam, A. (2020) · Physical review. D/Physical review. D. · doi:10.1103/physrevd.102.066008 · Cited by 30 · see citing works
Homology conditions for RT surfaces in double holography
Neuenfeld, D. (2022) · Classical and Quantum Gravity · doi:10.1088/1361-6382/ac51e7 · Cited by 36 · see citing works
HPS meets AMPS: how soft hair dissolves the firewall
Pasterski, S., & Verlinde, H. (2021) · Journal of High Energy Physics · doi:10.1007/jhep09(2021)099 · Cited by 24 · see citing works
Islands far outside the horizon
Raphael Bousso, A., & Penington, G. (2024) · Journal of High Energy Physics · doi:10.1007/jhep11(2024)164 · Cited by 28 · see citing works
Self-citationReal-space RG, error correction and Petz map
Furuya, K., Lashkari, N., & Ouseph, S. (2022) · Journal of High Energy Physics · doi:10.1007/jhep01(2022)170 · Cited by 19 · see citing works
Twice upon a time: timelike-separated quantum extremal surfaces
Engelhardt, N., Penington, G., & Shahbazi-Moghaddam, A. (2024) · Journal of High Energy Physics · doi:10.1007/jhep01(2024)033 · Cited by 22 · see citing works
Self-citationAguilar-Gutierrez, S. E., Chatwin-Davies, A., Hertog, T., Pinzani-Fokeeva, N., & Robinson, B. (2021) · Journal of High Energy Physics · doi:10.1007/jhep11(2021)212 · Cited by 18 · see citing works
Levine, A., Shahbazi-Moghaddam, A., & Soni, R. M. (2021) · Journal of High Energy Physics · doi:10.1007/jhep06(2021)134 · Cited by 18 · see citing works
Ghodrati, M. (2021) · Physical Review D · doi:10.1103/physrevd.104.046004 · Cited by 14 · see citing works
Holographic coarse-graining: correlators from the entanglement wedge and other reduced geometries
Güijosa, A., Olivas, Y. D., & Pedraza, J. F. (2022) · Journal of High Energy Physics · doi:10.1007/jhep08(2022)118 · Cited by 14 · see citing works
More of the bulk from extremal area variations
Bao, N., Cao, C., Fischetti, S., Pollack, J., & Zhong, Y. (2020) · Classical and Quantum Gravity · doi:10.1088/1361-6382/abcfd0 · Cited by 13 · see citing works
Petz reconstruction in random tensor networks
Jia, H. F., & Rangamani, M. (2020) · Journal of High Energy Physics · doi:10.1007/jhep10(2020)050 · Cited by 12 · see citing works
Holography and localization of information in quantum gravity
Bahiru, E., Belin, A., Papadodimas, K., Sárosi, G., & Vardian, N. (2024) · Journal of High Energy Physics · doi:10.1007/jhep05(2024)261 · Cited by 23 · see citing works
Noise-adapted recovery circuits for quantum error correction
Biswas, D., Vaidya, G. M., & Mandayam, P. (2024) · Physical Review Research · doi:10.1103/physrevresearch.6.043034 · Cited by 10 · see citing works
Python’s lunches in Jackiw-Teitelboim gravity with matter
Dongsu Bak, A., Kim, C., Yi, S.-H., & Yoon, J. (2022) · Journal of High Energy Physics · doi:10.1007/jhep04(2022)175 · Cited by 10 · see citing works
Quantum error correction and holographic information from bilocal holography
Koch, R. D. M., Gandote, E., Tahiridimbisoa, N. H., & Zyl, H. J. R. V. (2021) · Journal of High Energy Physics · doi:10.1007/jhep11(2021)192 · Cited by 8 · see citing works
Optimality Condition for the Petz Map
Li, B., Wang, Z., Zheng, G., Wong, Y., & Jiang, L. (2025) · Physical Review Letters · doi:10.1103/physrevlett.134.200602 · Cited by 7 · see citing works
Zhao, Y. (2020) · Journal of High Energy Physics · doi:10.1007/jhep11(2020)038 · Cited by 7 · see citing works
Explicit reconstruction of the entanglement wedge via the Petz map
Bahiru, E., & Vardian, N. (2023) · Journal of High Energy Physics · doi:10.1007/jhep07(2023)025 · Cited by 8 · see citing works
Antonini, S., Chen, C.-H., Maxfield, H., & Penington, G. (2025) · Journal of High Energy Physics · doi:10.1007/jhep10(2025)034 · Cited by 8 · see citing works
Self-citationEntanglement islands and cutoff branes from path-integral optimization
Chandra, A., Li, Z., & Wen, Q. (2024) · Journal of High Energy Physics · doi:10.1007/jhep07(2024)069 · Cited by 6 · see citing works
Entanglement Islands from Hilbert space reduction
Basu, D., Wen, Q., & Zhou, S. (2025) · The European Physical Journal Plus · doi:10.1140/epjp/s13360-025-06320-1 · Cited by 17 · see citing works
Nonperturbative gravity corrections to bulk reconstruction
Gesteau, E., & Kang, M. J. (2023) · Journal of Physics A Mathematical and Theoretical · doi:10.1088/1751-8121/acef7d · Cited by 11 · see citing works
Quantum reversal: a general theory of coherent quantum absorbers
Tsang, M. (2025) · Quantum · doi:10.22331/q-2025-02-26-1650 · Cited by 6 · see citing works
On the underlying nonrelativistic nature of relativistic holography
Güijosa, A. (2025) · Journal of High Energy Physics · doi:10.1007/jhep08(2025)139 · Cited by 11 · see citing works
Microstate distinguishability, quantum complexity, and the eigenstate thermalization hypothesis
Bao, N., Pollack, J., Wakeham, D., & Wildenhain, E. (2021) · Classical and Quantum Gravity · doi:10.1088/1361-6382/ac0e17 · Cited by 5 · see citing works
Large and small corrections to the JLMS Formula from replica wormholes
Kudler-Flam, J., & Rath, P. (2022) · Journal of High Energy Physics · doi:10.1007/jhep08(2022)189 · Cited by 5 · see citing works
A teleportation protocol in Schwarzschild-de Sitter space
Aguilar-Gutierrez, S. E., Espíndola, R., & Morvan, E. (2025) · Journal of High Energy Physics · doi:10.1007/jhep03(2025)095 · Cited by 9 · see citing works
Modular flow in JT gravity and entanglement wedge reconstruction
Gao, P. (2024) · Journal of High Energy Physics · doi:10.1007/jhep06(2024)151 · Cited by 4 · see citing works
The mechanism behind the information encoding for islands
Geng, H. (2026) · Journal of High Energy Physics · doi:10.1007/jhep03(2026)037 · Cited by 9 · see citing works
Fluctuation in the fidelity of information recovery from Hawking radiation
Miyaji, M., & Yano, K. (2024) · Physical review. D/Physical review. D. · doi:10.1103/physrevd.109.086011 · Cited by 3 · see citing works
Time‐Symmetric Correlations for Open Quantum Systems
Parzygnat, A. J., & Fullwood, J. (2025) · Annalen der Physik · doi:10.1002/andp.202500221 · Cited by 5 · see citing works
Probing the Page transition via approximate quantum error correction
Zhong, H. (2025) · Journal of High Energy Physics · doi:10.1007/jhep01(2025)086 · Cited by 2 · see citing works
Causal shadow and non-local modular flow: from degeneracy to perturbative genesis by correlation
Chen, L., & Wang, H. (2023) · Journal of High Energy Physics · doi:10.1007/jhep02(2023)052 · Cited by 5 · see citing works
Explicit decoders using fixed-point amplitude amplification based on QSVT
Utsumi, T., & Nakata, Y. (2026) · Quantum · doi:10.22331/q-2026-03-13-2024
Quantum Extremal Surfaces and the Page Curve
Mahajan, R. (2025) · Springer Series in Astrophysics and Cosmology · doi:10.1007/978-981-96-6170-1_16
Final State Projection and Non-isometric Codes
Akers, C. (2025) · Springer Series in Astrophysics and Cosmology · doi:10.1007/978-981-96-6170-1_17
Balasubramanian, V., & Yildirim, T. P. (2026) · Physical review. D/Physical review. D. · doi:10.1103/p7wt-47rj
Nonperturbative gravity corrections to bulk reconstruction
Gesteau, E., & Kang, M. J. (2021) · arXiv · doi:10.48550/arxiv.2112.12789 · Cited by 6
- Authors
- Chen, C.-F., Penington, G., & Salton, G.
- Affiliations
- California Institute of Technology (US)
- Corresponding author
- Chen, Chi-Fang
- Venue
- Journal of High Energy Physics
- Published
- 2020-01-28
- Volume
- 2020
- Issue
- 1
- ISSN
- 1029-8479 (ISSN-L)
- OpenAlex
- W2929692894
- Cited by
- 54
- References
- 27
- Citations by year
- 2026: 3 · 2025: 10 · 2024: 7 · 2023: 9 · 2022: 9 · 2021: 9 · 2020: 7
- FWCI
- 3.76
- Type
- journal article
- Language
- en
- Open access
- diamond
- doi.org
- Locations
- Journal of High Energy Physics (publishedVersion, cc-by)
- arXiv (Cornell University) (submittedVersion)
- CaltechAUTHORS (California Institute of Technology) (submittedVersion, cc-by)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
- arXiv (Cornell University)
- Funders
- U.S. Department of Energy (DESC0018407)
- Simons Foundation
- California Institute of Technology
- Institute for Quantum Information and Matter, California Institute of Technology
- Air Force Office of Scientific Research (FA9550-, FA9550-16-1-0082, FA9550-16, -16-1-, FA9550-16-1)
- SLAC National Accelerator Laboratory
- Topics
- Physical Sciences › Physics and Astronomy › Nuclear and High Energy Physics › Black Holes and Theoretical Physics
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Quantum many-body systems
- Physical Sciences › Mathematics › Mathematical Physics › Advanced Operator Algebra Research
- Keywords
- entanglement wedge reconstruction, AdS/CFT correspondence, quantum error correction, holography, quantum information
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review