REVIEW 4 minor 88 references
Reviewed by Pith at T0; open to challenge.
T0 means a machine referee read the full paper against a public rubric. The mark states how deep the mechanical check went, never who wrote it. the ladder, T0–T4 →
T0 review · grok-4.5
Quantum dense network coding computes modular addition with half the qubits of classical bits and only works when both entanglement and quantum channels are present.
2026-07-10 12:32 UTC pith:Z7GRKYQZ
load-bearing objection Clean quadratic signaling-dimension advantage for multiaccess function computation, fully proved and tight, plus a natural MDI key-growing spin-off; solid mid-tier network QI paper that deserves referees.
Communication Advantages from Quantum Dense Network Coding
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
An entanglement-assisted quantum multiaccess network with signaling dimensions (2^n, 2^n) implements ditwise addition modulo 2^n with success probability 1, while every weaker resource class—classical, entanglement-assisted classical, nonsignaling-assisted classical, or unassisted quantum—is bounded by success probability at most 1/2^n.
What carries the argument
Tightly network-codeable groups: groups of order d^{2} that admit a projective unitary representation by discrete Weyl operators on C^d; the representation turns the group product into a perfect Bell-state measurement at the receiver.
Load-bearing premise
The cryptographic key-growing rate assumes the two parties already share a known entangled state whose purification remains independent of any eavesdropper after the honest encoding maps are applied.
What would settle it
Measure the success probability of computing two-pair modular addition with n-qubit channels: if a classical or entanglement-free quantum strategy ever exceeds 1/2^n while the dense-network-coding strategy falls below 1 under controlled noise, the claimed separation is false.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper introduces quantum dense network coding (DNC): an entanglement-assisted quantum multiaccess protocol that computes certain non-Boolean functions (ditwise modular addition ⊕²_{2^{n}} and, more generally, the group operation of tightly network-codeable groups) with success probability 1 using signaling dimensions (2^{n},2^{n}). Matching upper bounds show that every weaker resource class—classical, entanglement-assisted classical, nonsignaling-assisted classical, or unassisted quantum—is limited to success probability ≤ 1/2^{n} (Theorem 2 / Theorem 9). The advantage is shown to require both shared entanglement and quantum communication, to be robust to diamond-norm noise (Theorem 3 / Theorem 11), and to amplify exponentially with the number of pairwise-entangled senders (Theorem 4). A secondary application, measurement-device-independent quantum key growing, is derived from the same algebraic structure and given a one-shot and asymptotic security analysis (Appendix I).
Significance. If correct, the work supplies a clean, tight quadratic gap in signaling dimension for multiaccess network computation that cannot be obtained from superdense coding alone (the receiver shares no entanglement). The proofs are fully explicit: Protocol 1/3 correctness follows from the projective representation property of discrete Weyl operators; the matching upper bounds rest on a reduction to guessing probability, equality of guessing probabilities for doubly-conditionally-bijective functions, and Frenkel–Weiner / nonsignaling dimension bounds. Noise robustness is controlled by diamond-norm continuity, and the multi-sender amplification is multiplicative. The cryptographic application is secondary but conceptually natural. The combination of matching bounds, noise robustness, and an explicit algebraic characterization of the functions that admit DNC makes the result a solid contribution to quantum network information theory.
minor comments (4)
- Figure 2 caption and surrounding text: the concrete lower bound P^f_S(n,e,p) is written with a factor of 2 that is not immediately transparent from Theorem 3; a one-sentence derivation (or pointer to the corresponding calculation in Appendix G) would help the reader verify the plotted curves.
- Section 2.2.1 / Appendix B: the term “tightly network codeable” is introduced without a short forward reference to the minimality claim (Eq. 42). A parenthetical remark would improve readability.
- Appendix I, Protocol 4 and Lemma 71: the security analysis assumes a known (or testable) initial state. A brief clarifying sentence that online testing would convert the protocol into a full QKD scheme (as already noted in the main text) would prevent misreading of the key-growing claim.
- Notation: the signaling-dimension parameterization switches between (2^{n},2^{n}) in the main text and (d,d) in the appendices; a single consistent convention, or an explicit conversion sentence, would reduce cognitive load.
Circularity Check
Minor self-citation to authors' prior numerical survey for the motivating example; all load-bearing theorems (Protocols 1/3, Theorems 1-2/6/9, Lemmas 28/31-32, Theorems 7-8) are derived self-contained from first principles with no fitted parameters or definitional loops.
specific steps
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self citation load bearing
[Section 1 (Introduction), paragraph beginning 'Recently, Doolittle et al. [15]']
"Recently, Doolittle et al. [15] developed a framework for studying communication advantages in quantum networks, and numerically surveyed communication advantages over a broad range of communication network topologies and quantum resource configurations. The survey found that the strongest communication advantages occurred in networks that have many senders and a single receiver. Specifically, the authors provide an example in which the receiver computes the bitwise XOR between each sender's two-bit inputs... In this work, we generalize the bitwise XOR protocol from reference [15] to develop d"
The motivating example and the name 'dense network coding' are imported from the authors' own prior numerical survey [15]. While the subsequent analytic proofs (Theorems 1-2, 6, 9) stand independently, the paper presents the protocol as a generalization of that self-cited example rather than deriving the existence of an advantage from first principles alone; the citation is therefore a minor self-referential load for the narrative framing, though not for the mathematical claims.
full rationale
The paper's central communication-advantage claims rest on explicit algebraic constructions (discrete Weyl operators / projective representations of TNC groups, Eqs. 3-11 and Protocol 3/Theorem 6) and independent information-theoretic bounds (reduction of success probability to guessing probability via Lemma 28; equality for doubly-conditionally-bijective functions via Lemmas 31-32; Frenkel-Weiner and nonsignaling decompositions via Theorems 7-8/Proposition 44). These steps do not reduce to inputs by construction, nor do they invoke uniqueness theorems or ansatze from the authors' prior work. The sole self-citation ([15]) supplies only the numerical observation that motivated generalizing the bitwise-XOR example; the analytic proofs, tightness for even n (Corollary 46), noise robustness (Theorem 11), multi-sender amplification (Theorem 12/Corollary 64), and MDI-QKG rate (Theorem 13/Lemma 71) are derived independently and parameter-free. No fitted quantities are renamed as predictions, and the cryptographic security reduces to ordinary conditional min-entropy of the encoded state. Consequently the derivation chain is free of circularity beyond a non-load-bearing motivational citation, warranting score 1.
Axiom & Free-Parameter Ledger
axioms (4)
- standard math Quantum channels are completely positive trace-preserving maps; the diamond norm metrizes them.
- standard math The guessing probability equals the exponential of the negative conditional min-entropy (König–Renner–Schaffner).
- domain assumption A group of order d^{2} admits a projective unitary representation on ℂ^{d} if and only if it is the index group of a nice error basis (Knill).
- standard math Nonsignaling bipartite channels that are classical on one side are semilocalizable (Eggeling–Schlingemann–Werner).
invented entities (2)
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quantum dense network coding (Protocol 1 / Protocol 3)
independent evidence
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measurement-device-independent quantum key growing (Protocol 2 / Protocol 4)
independent evidence
read the original abstract
A central problem in quantum information theory is understanding how quantum resources can be used to communicate information more efficiently than classical resources. We introduce quantum dense network coding -- a protocol that transmits the output of a non-Boolean function to a receiver using provably half as many qubits as bits for each sender by not transmitting the entirety of the function inputs. We show this advantage requires both shared entanglement and quantum communication, is robust to noise, and the gap in success probability between quantum and classical communication can be amplified exponentially in the number of senders. Finally, we show that dense network coding gives rise to a novel, information-theoretically secure, quantum cryptographic protocol, which we call measurement-device-independent quantum key growing.
Figures
Reference graph
Works this paper leans on
-
[1]
Available: https://link.aps.org/doi/10.1103/PhysRevLett
Charles H. Bennett and Stephen J. Wiesner. Communication via one- and two-particle operators on einstein-podolsky-rosen states. Phys. Rev. Lett., 69:2881–2884, Nov 1992. doi: 10.1103/PhysRevLett. 69.2881. URLhttps://link.aps.org/doi/10.1103/PhysRevLett.69.2881
-
[2]
Igor Devetak, Aram W. Harrow, and Andreas J. Winter. A resource framework for quantum shannon theory. IEEE Transactions on Information Theory, 54(10):4587–4618, 2008. doi: 10.1109/TIT.2008. 928980
-
[3]
Alexander S. Holevo. Bounds for the quantity of information transmitted by a quantum communica- tion channel. Problemy Peredachi Informatsii, 9, 1973. URLhttps://api.semanticscholar.org/ CorpusID:118312737
work page 1973
-
[4]
C.H. Bennett, P.W. Shor, J.A. Smolin, and A.V. Thapliyal. Entanglement-assisted capacity of a quan- tum channel and the reverse shannon theorem. IEEE Transactions on Information Theory, 48(10): 2637–2655, 2002. doi: 10.1109/TIT.2002.802612
-
[5]
Cubitt, Debbie Leung, William Matthews, and Andreas Winter
Toby S. Cubitt, Debbie Leung, William Matthews, and Andreas Winter. Zero-error channel capacity and simulation assisted by non-local correlations. IEEE Transactions on Information Theory, 57(8): 5509–5523, 2011. doi: 10.1109/TIT.2011.2159047
-
[6]
P´ eter E. Frenkel and Mih´ aly Weiner. Classical information storage in an n-level quantum sys- tem. Communications in Mathematical Physics, 340(2):563–574, September 2015. doi: 10.1007/ s00220-015-2463-0. URLhttps://doi.org/10.1007/s00220-015-2463-0
-
[7]
Michele Dall’Arno, Sarah Brandsen, Alessandro Tosini, Francesco Buscemi, and Vlatko Vedral. No- hypersignaling principle. Phys. Rev. Lett., 119:020401, Jul 2017. doi: 10.1103/PhysRevLett.119.020401. URLhttps://link.aps.org/doi/10.1103/PhysRevLett.119.020401
-
[8]
Certifying the classical simulation cost of a quantum channel
Brian Doolittle and Eric Chitambar. Certifying the classical simulation cost of a quantum channel. Phys. Rev. Res., 3:043073, Oct 2021. doi: 10.1103/PhysRevResearch.3.043073. URLhttps://link. aps.org/doi/10.1103/PhysRevResearch.3.043073
-
[9]
The communication value of a quantum channel
Eric Chitambar, Ian George, Brian Doolittle, and Marius Junge. The communication value of a quantum channel. IEEE Transactions on Information Theory, 69(3):1660–1679, 2023. doi: 10.1109/TIT.2022. 3218540
-
[10]
Quantum Entanglement and the Communication Complexity of the Inner Product Function, page 61–74
Richard Cleve, Wim van Dam, Michael Nielsen, and Alain Tapp. Quantum Entanglement and the Communication Complexity of the Inner Product Function, page 61–74. Springer Berlin Heidelberg,
-
[11]
ISBN 9783540492085. doi: 10.1007/3-540-49208-9 4. URLhttp://dx.doi.org/10.1007/ 3-540-49208-9_4
-
[12]
Testing dimension and nonclassicality in communication networks
Joseph Bowles, Nicolas Brunner, and Marcin Paw lowski. Testing dimension and nonclassicality in communication networks. Phys. Rev. A, 92:022351, Aug 2015. doi: 10.1103/PhysRevA.92.022351. URLhttps://link.aps.org/doi/10.1103/PhysRevA.92.022351
-
[13]
Building multiple access channels with a single particle
Yujie Zhang, Xinan Chen, and Eric Chitambar. Building multiple access channels with a single particle. Quantum, 6:653, February 2022. ISSN 2521-327X. doi: 10.22331/q-2022-02-16-653. URLhttp: //dx.doi.org/10.22331/q-2022-02-16-653. 13
-
[14]
Alhejji, Joshua Levin, and Graeme Smith
Felix Leditzky, Mohammad A. Alhejji, Joshua Levin, and Graeme Smith. Playing games with multiple access channels. Nature Communications, 11(1), March 2020. ISSN 2041-1723. doi: 10.1038/s41467-020-15240-w. URLhttp://dx.doi.org/10.1038/s41467-020-15240-w
-
[15]
Harry Buhrman, Richard Cleve, John Watrous, and Ronald De Wolf. Quantum fingerprinting. Physical review letters, 87(16):167902, 2001
work page 2001
-
[16]
An Operational Framework for Nonclassicality in Quantum Communication Networks
Brian Doolittle, Felix Leditzky, and Eric Chitambar. Operational nonclassicality in quantum communi- cation networks. arXiv preprint arXiv:2403.02988, 2024. URLhttps://arxiv.org/abs/2403.02988
work page internal anchor Pith review Pith/arXiv arXiv 2024
-
[17]
R. Ahlswede, Ning Cai, S.-Y.R. Li, and R.W. Yeung. Network information flow. IEEE Transactions on Information Theory, 46(4):1204–1216, 2000. doi: 10.1109/18.850663
-
[18]
Network coding: an introduction
Tracey Ho and Desmond Lun. Network coding: an introduction. Cambridge University Press, 2008
work page 2008
-
[19]
Quantum nonlocality as an axiom
Sandu Popescu and Daniel Rohrlich. Quantum nonlocality as an axiom. Foundations of Physics, 24(3): 379–385, 1994
work page 1994
-
[20]
M. Piani, M. Horodecki, P. Horodecki, and R. Horodecki. Properties of quantum nonsignaling boxes. Phys. Rev. A, 74:012305, Jul 2006. doi: 10.1103/PhysRevA.74.012305. URLhttps://link.aps.org/ doi/10.1103/PhysRevA.74.012305
-
[21]
The Theory of Quantum Information
John Watrous. The Theory of Quantum Information. Cambridge University Press, 2018. doi: 10.1017/ 9781316848142
work page 2018
-
[22]
Capacity of quantum private information retrieval with multiple servers
Seunghoan Song and Masahito Hayashi. Capacity of quantum private information retrieval with multiple servers. IEEE Transactions on Information Theory, 67(1):452–463, 2021. doi: 10.1109/TIT.2020. 3022515
-
[23]
All teleportation and dense coding schemes
Reinhard F Werner. All teleportation and dense coding schemes. Journal of Physics A: Mathematical and General, 34(35):7081–7094, 2001
work page 2001
-
[24]
Group Representations, Error Bases and Quantum Codes
Emanuel Knill. Group representations, error bases and quantum codes. arXiv preprint quant-ph/9608049, 1996
work page internal anchor Pith review Pith/arXiv arXiv 1996
-
[25]
Andreas A Klappenecker and M Rotteler. Beyond stabilizer codes. i. nice error bases. IEEE Transactions on Information Theory, 48(8):2392–2395, 2002
work page 2002
-
[26]
Charles H. Bennett and Gilles Brassard. Quantum cryptography: Public key distribution and coin tossing. Theoretical Computer Science, 560:7–11, December 2014. ISSN 0304-3975. doi: 10.1016/j.tcs. 2014.05.025. URLhttp://dx.doi.org/10.1016/j.tcs.2014.05.025
-
[27]
The quantum postulate and the recent development of atomic theory1
Niels Bohr. The quantum postulate and the recent development of atomic theory1. Nature, 121(3050): 580–590, April 1928
work page 1928
-
[28]
Charles H. Bennett. Quantum cryptography using any two nonorthogonal states. Phys. Rev. Lett., 68:3121–3124, May 1992. doi: 10.1103/PhysRevLett.68.3121. URLhttps://link.aps.org/doi/10. 1103/PhysRevLett.68.3121
-
[29]
Quantum cryptography based on bell’s theorem
Artur K Ekert. Quantum cryptography based on bell’s theorem. Physical review letters, 67(6):661, 1991
work page 1991
-
[30]
Discussion of probability relations between separated systems
Erwin Schr¨ odinger. Discussion of probability relations between separated systems. In Mathematical proceedings of the cambridge philosophical society, volume 31, pages 555–563. Cambridge University Press, 1935
work page 1935
-
[31]
Measurement-device-independent quantum key distribution
Hoi-Kwong Lo, Marcos Curty, and Bing Qi. Measurement-device-independent quantum key distribution. Physical review letters, 108(13):130503, 2012. 14
work page 2012
-
[32]
Fully device-independent quantum key distribution
Umesh Vazirani and Thomas Vidick. Fully device-independent quantum key distribution. Physical Review Letters, 113(14), Sept 2014. ISSN 1079-7114. doi: 10.1103/physrevlett.113.140501. URL http://dx.doi.org/10.1103/PhysRevLett.113.140501
-
[33]
On the einstein podolsky rosen paradox
John S Bell. On the einstein podolsky rosen paradox. Physics Physique Fizika, 1(3):195, 1964
work page 1964
-
[34]
Distillation of secret key and entanglement from quantum states
Igor Devetak and Andreas Winter. Distillation of secret key and entanglement from quantum states. Proceedings of the Royal Society A: Mathematical, Physical and engineering sciences, 461(2053):207– 235, 2005
work page 2053
-
[35]
N-sum box: An abstraction for linear computation over many-to-one quantum networks
Matteo Allaix, Yuxiang Lu, Yuhang Yao, Tefjol Pllaha, Camilla Hollanti, and Syed Jafar. N-sum box: An abstraction for linear computation over many-to-one quantum networks. InGLOBECOM 2023 - 2023 IEEE Global Communications Conference, pages 5457–5462, 2023. doi: 10.1109/GLOBECOM54140. 2023.10437170
-
[36]
Yuhang Yao and Syed A. Jafar. The capacity of classical summation over a quantum mac with arbitrarily distributed inputs and entanglements. IEEE Transactions on Information Theory, 70(9):6350–6370,
-
[37]
doi: 10.1109/TIT.2024.3397917
-
[38]
Yuhang Yao and Syed A. Jafar. On the capacity of vector linear computation over a noiseless quantum multiple-access channel with entangled transmitters. IEEE Transactions on Quantum Engineering, 6: 1–20, 2025. doi: 10.1109/TQE.2025.3620628
-
[39]
Precoding based protocols for entanglement assisted liner computation over a quantum mac
Ruoyu Meng and Aditya Ramamoorthy. Precoding based protocols for entanglement assisted liner computation over a quantum mac. In ISIT 2026, 2026. To appear
work page 2026
-
[40]
Elena Polozova and Frederick W. Strauch. Higher-dimensional bell inequalities with noisy qudits. Physical Review A, 93(3), March 2016. ISSN 2469-9934. doi: 10.1103/physreva.93.032130. URL http://dx.doi.org/10.1103/PhysRevA.93.032130
-
[41]
Verena Yacoub, Niraj Kumar, Iordanis Kerenidis, and Eleni Diamanti. Experimental demonstration of quantum advantage in communication complexity for euclidean distance problem, 2026. URLhttps: //arxiv.org/abs/2605.31516
work page internal anchor Pith review Pith/arXiv arXiv 2026
-
[42]
The operational meaning of min-and max- entropy
Robert Konig, Renato Renner, and Christian Schaffner. The operational meaning of min-and max- entropy. IEEE Transactions on Information theory, 55(9):4337–4347, 2009
work page 2009
-
[43]
Ian George, Jie Lin, Thomas van Himbeeck, Kun Fang, and Norbert L¨ utkenhaus. Finite-key analysis of quantum key distribution with characterized devices using entropy accumulation. Quantum, 9:1941, December 2025. ISSN 2521-327X. doi: 10.22331/q-2025-12-12-1941. URLhttp://dx.doi.org/10. 22331/q-2025-12-12-1941
-
[44]
Semicausal operations are semilocalizable
Tilo Eggeling, Dirk Schlingemann, and Reinhard F Werner. Semicausal operations are semilocalizable. EPL (Europhysics Letters), 57(6):782–788, 2002
work page 2002
-
[45]
Mark M Wilde. Quantum information theory. Cambridge University Press, 2013. doi: 10.1017/ CBO9781139525343
work page 2013
-
[46]
Quantum Information Processing with Finite Resources -- Mathematical Foundations
Marco Tomamichel. Quantum information processing with finite resources: mathematical foundations, volume 5. Springer, 2015. doi: 10.1007/978-3-319-21891-5. All references are to version 5 on the arXiv: https://arxiv.org/abs/1504.00233v5
work page internal anchor Pith review Pith/arXiv arXiv doi:10.1007/978-3-319-21891-5 2015
-
[47]
Theoretical framework for quantum networks
Giulio Chiribella, Giacomo Mauro D’Ariano, and Paolo Perinotti. Theoretical framework for quantum networks. Physical Review A—Atomic, Molecular, and Optical Physics, 80(2):022339, 2009. 15
work page 2009
-
[48]
Some complexity questions related to distributive computing(preliminary re- port)
Andrew Chi-Chih Yao. Some complexity questions related to distributive computing(preliminary re- port). In Proceedings of the Eleventh Annual ACM Symposium on Theory of Computing, STOC ’79, page 209–213, New York, NY, USA, 1979. Association for Computing Machinery. ISBN 9781450374385. doi: 10.1145/800135.804414. URLhttps://doi.org/10.1145/800135.804414
-
[49]
Nonlocality and communication complexity
Harry Buhrman, Richard Cleve, Serge Massar, and Ronald de Wolf. Nonlocality and communication complexity. Rev. Mod. Phys., 82:665–698, Mar 2010. doi: 10.1103/RevModPhys.82.665. URLhttps: //link.aps.org/doi/10.1103/RevModPhys.82.665
-
[50]
Quantum state discrimination and its applications
Joonwoo Bae and Leong-Chuan Kwek. Quantum state discrimination and its applications. Journal of Physics A: Mathematical and Theoretical, 48(8):083001, January 2015. ISSN 1751-8121. doi: 10.1088/ 1751-8113/48/8/083001. URLhttp://dx.doi.org/10.1088/1751-8113/48/8/083001
-
[51]
A Framework for Non-Asymptotic Quantum Information Theory
Marco Tomamichel. A Framework for Non-Asymptotic Quantum Information Theory. PhD thesis, ETH Zurich, 2013. URLhttps://arxiv.org/abs/1203.2142
work page internal anchor Pith review Pith/arXiv arXiv 2013
-
[52]
Unitary error bases: Constructions, equivalence, and appli- cations
Andreas Klappenecker and Martin R¨ otteler. Unitary error bases: Constructions, equivalence, and appli- cations. In International Symposium on Applied Algebra, Algebraic Algorithms, and Error-Correcting Codes, pages 139–149. Springer, 2003
work page 2003
-
[53]
Handbook of global optimization
Reiner Horst and Panos M Pardalos, editors. Handbook of global optimization. Nonconvex Optimization and Its Applications. Springer, Dordrecht, Netherlands, 1995 edition, November 1994
work page 1995
-
[54]
Handbook of combinatorial designs
Jeffrey H Dinitz. Handbook of combinatorial designs. Chapman & Hall/CRC, 2007
work page 2007
-
[55]
Uniform continuity bound for sandwiched r´ enyi conditional entropy
Ashutosh Marwah and Fr´ ed´ eric Dupuis. Uniform continuity bound for sandwiched r´ enyi conditional entropy. Journal of Mathematical Physics, 63(5), May 2022. ISSN 1089-7658. doi: 10.1063/5.0088507. URLhttp://dx.doi.org/10.1063/5.0088507
-
[56]
Andreas Bluhm, ´Angela Capel, Paul Gondolf, and Tim M¨ obus. Unified framework for continuity of sandwiched r´ enyi divergences.Annales Henri Poincar´ e, 27(1):1–50, December 2024. ISSN 1424-0661. doi: 10.1007/s00023-024-01519-x. URLhttp://dx.doi.org/10.1007/s00023-024-01519-x
-
[57]
Quantum computations: algorithms and error correction
A Yu Kitaev. Quantum computations: algorithms and error correction. Russian Mathematical Surveys, 52(6):1191, dec 1997. doi: 10.1070/RM1997v052n06ABEH002155. URLhttps://doi.org/10.1070/ RM1997v052n06ABEH002155
-
[58]
Sumeet Khatri and Mark M. Wilde. Principles of quantum communication theory: A modern approach,
-
[59]
URLhttps://arxiv.org/abs/2011.04672
work page internal anchor Pith review Pith/arXiv arXiv 2011
-
[60]
Security in quantum cryptography
Christopher Portmann and Renato Renner. Security in quantum cryptography. Reviews of Modern Physics, 94(2), June 2022. ISSN 1539-0756. doi: 10.1103/revmodphys.94.025008. URLhttp://dx. doi.org/10.1103/RevModPhys.94.025008
-
[61]
A largely self-contained and complete security proof for quantum key distribution
Marco Tomamichel and Anthony Leverrier. A largely self-contained and complete security proof for quantum key distribution. Quantum, 1:14, 2017
work page 2017
-
[62]
Ernest Y. Z. Tan. Prospects for device-independent quantum key distribution, 2024. URLhttps: //arxiv.org/abs/2111.11769
work page internal anchor Pith review Pith/arXiv arXiv 2024
-
[63]
A fully quantum asymptotic equipartition property
Marco Tomamichel, Roger Colbeck, and Renato Renner. A fully quantum asymptotic equipartition property. IEEE Transactions on information theory, 55(12):5840–5847, 2009
work page 2009
-
[64]
Noiseless coding of correlated information sources
David Slepian and Jack Wolf. Noiseless coding of correlated information sources. IEEE Transactions on information Theory, 19(4):471–480, 1973. 16 AcknowledgmentsThe authors thank Haneul Kim, Felix Leditzky, and Eric Chitambar for insightful discussions. This project is supported by Aliro Technologies, Inc. This project is supported by the Ministry of Educ...
work page 1973
-
[65]
the noiselessquantumchannel on ad-dimensional quantum system, which we denote id d := idCd→Cd, and
-
[66]
tightly network codeable (TNC) groups,
the noiselessclassicalchannel on ad-dimensional quantum system, which we denote ∆ d. In the above, ∆ d is really thed-dimensional completely dephasing channel with respect to some implicit computational basis. This is the appropriate choice for classical communication as it will transmit all classical information in that basis noiselessly but dephase any ...
-
[67]
Associativity: (g·h)·f=g·(h·f) for allg, h, f∈G,
-
[68]
Identity: there existse∈Gsuch thatg·e=e·g=gfor allg∈G, and
-
[69]
Inverse: for eachg∈G, there exists an elementg −1 ∈Gsuch thatg·g −1 =e=g −1 ·g. 23 For the rest of this section, we will consider sets of unitaries indexed by the elements ofG, e.g.{U g}g∈G. It follows that one may express the index of the unitary in terms of other group elements and the group operation, e.g.U g·h isU g′ whereg ′ =g·h. With the notation f...
-
[70]
These representation-theoretic conditions on the group are useful due to the following
There exist{ω(g, h)} g,h∈G ⊂U(C) such that UgUh =ω(g, h)U g·h ∀g, h∈G .(38) We call such a group a tightly network codeable (TNC) group and the setUits TNC representation. These representation-theoretic conditions on the group are useful due to the following. Proposition 22.Let (G,·) be a TNC group of orderd 2 andU ⊂U(d) its TNC representation. Define the...
-
[71]
On inputg, Sender 1 appliesU g to their local system of|Φ⟩
-
[72]
On inputh, Sender 2 appliesU T h to their local system of|Φ⟩
-
[73]
Senders 1 and 2 forward their systems to the receiver. 24
-
[74]
The receiver applies theG-Bell state measurement (41) to its received systems obtaining outcome ˆg∈G, which it outputs as the answer. Theorem 6.Let (G,·) be a TNC group of orderd 2 andf(g, h) :=g·hbe the function defined by the group operation. Protocol 3 computesfperfectly. That isP f S (QE(d, d)) = 1. Moreover, this strategy is symmetrically minimal in ...
-
[75]
The groupGis called the index group of the nice error basis
For allg, h∈G, there existsω(g, h)∈C\ {0}such thatU gUh =ω(g, h)U g·h. The groupGis called the index group of the nice error basis. Proposition 26.A group (G,·) is the index group of a nice error basis if and only if it is a TNC group. Proof.(=⇒) Let (G,·) be the index group of a nice error basis. Let{U g}g∈G be the corresponding nice error basis. We will...
-
[76]
In the case thatQ= 0, this is trivial, so we can assumeQ≥0 andQ̸= 0
This is a rather direct calculation that we provide. In the case thatQ= 0, this is trivial, so we can assumeQ≥0 andQ̸= 0. As we can always letQ Y E =aσ Y E wherea >0, it suffices to now consider the 7See (255) as an example 32 caseσ Y E ∈D(Y E), whereσ Y E =P y r(y)|y⟩ ⟨y| ⊗σ y E. Then U(I X ⊗σ Y E)U † = X x1,y1 |fy1(x1)⟩ ⟨x1| ⊗ |y1⟩ ⟨y1| ! · X x |x⟩ ⟨x| ...
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[77]
to replace the quantum channel with a classical channel with the same signaling dimension and shared randomness (Corollary 34), we then remove the shared randomness without loss of generality (Proposition 14), and finally we can use Item 5 of Proposition 17 to obtain a bound only in terms of the ability to guess the value ofx∈ Xand the size of the signali...
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[78]
for allx∈ X, the functionsf x :Y → Zdefined viaf x(y) =f(x, y) are bijections and
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[79]
for ally∈ Y, the functionsf y :X → Zdefined viaf y(x) =f(x, y) are bijections. Noting a DCB function requires|X |=|Y|=|Z|, we say a DCB function is of ordernif|X |=n. For motivation of the subsequent structural claims, we begin with examples of DCB functions that include those we showed can be computed using dense network coding in Section B. Example 39(E...
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[80]
The ideal state is replaced with an isotropic stateρ λ (recall (23))
discussion (0)
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