Abstract
Semidefinite programs (SDPs) are a framework for exact or approximate optimization with widespread application in quantum information theory. We introduce a new method for using reductions to construct integrality gaps for SDPs, meaning instances where the SDP value is far from the true optimum. These are based on new limitations on the sum-of-squares (SoS) hierarchy in approximating two particularly important sets in quantum information theory, where previously no \({\omega(1)}\) -round integrality gaps were known:
-
1.
The set of separable (i.e. unentangled) states, or equivalently, the \({2 \rightarrow 4}\) norm of a matrix.
-
2.
The set of quantum correlations; i.e. conditional probability distributions achievable with local measurements on a shared entangled state.
Integrality gaps for the \({2\rightarrow 4}\) norm had previously been sought due to its connection to Small-Set Expansion (SSE) and Unique Games (UG).
In both cases no-go theorems were previously known based on computational assumptions such as the Exponential Time Hypothesis (ETH) which asserts that 3-SAT requires exponential time to solve. Our unconditional results achieve the same parameters as all of these previous results (for separable states) or as some of the previous results (for quantum correlations). In some cases we can make use of the framework of Lee–Raghavendra–Steurer (LRS) to establish integrality gaps for any SDP extended formulation, not only the SoS hierarchy. Our hardness result on separable states also yields a dimension lower bound of approximate disentanglers, answering a question of Watrous and Aaronson et al.
These results can be viewed as limitations on the monogamy principle, the PPT test, the ability of Tsirelson-type bounds to restrict quantum correlations, as well as the SDP hierarchies of Doherty–Parrilo–Spedalieri, Navascues–Pironio–Acin, and Berta–Fawzi–Scholz. Indeed a wide range of past work in quantum information can be described as using an SDP on one of the above two problems and our results put broad limits on these lines of argument.
Similar content being viewed by others
References
Aaronson, S., Beigi, S., Drucker, A., Fefferman, B., Shor, P.: The power of unentanglement. In: Annual IEEE Conference on Computational Complexity, pp. 223–236 (2008). arXiv:0804.0802
Aaronson S., Beigi S., Drucker A., Fefferman B., Shor P.: The power of unentanglement. Theory Comput. 5(1), 1–42 (2009) arXiv:0804.0802
Altunbulak M., Klyachko A.: The Pauli principle revisited. Commun. Math. Phys. 282(2), 287–322 (2008) arXiv:0802.0918
Aubrun, G., Szarek, S.J.: Dvoretzky’s theorem and the complexity of entanglement detection (2015). arXiv:1510.00578
Barak, B.: Sum of squares upper bounds, lower bounds, and open questions (2014). https://www.boazbarak.org/sos/prev/files/all-notes.pdf. Accessed 26 Feb 2019
Barak, B., Brandão, F.G.S.L., Harrow, A.W., Kelner, J., Steurer, D., Zhou, Y.: (2012) Hypercontractivity, sum-of-squares proofs, and their applications. In: Proceedings of the 44th Symposium on Theory of Computing, STOC ’12, pp. 307–326. (2012). arXiv:1205.4484
Brassard G., Buhrman H., Linden N., Méthot A.A., Tapp A., Unger F.: Limit on nonlocality in any world in which communication complexity is not trivial. Phys. Rev. Lett. 96, 250401 (2006) arXiv:quant-ph/0508042
Bäuml S., Christandl M., Horodecki K., Winter A.: Limitations on quantum key repeaters. Nat. Commun. 6, 6908 (2015) arXiv:1402.5927
Brandão F.G.S.L., Christandl M., Yard J.: Faithful squashed entanglement. Commun. Math. Phys. 306(3), 805–830 (2011) arXiv:1010.1750
Beigi, S.: NP vs QMA_log(2). 10(1&2), 0141–0151 (2010). arXiv:0810.5109
Bell J.S.: On the Einstein–Podolsky–Rosen paradox. Physics 1(3), 195–200 (1964)
Berta, M., Fawzi, O., Scholz, V.B.: Quantum bilinear optimization (2015). arXiv:1506.08810
Bhattiprolu, V., Guruswami, V., Lee, E.: Sum-of-squares certificates for maxima of random tensors on the sphere. In: LIPIcs-Leibniz International Proceedings in Informatics, Schloss Dagstuhl-Leibniz-Zentrum fuer Informatik, vol. 81 (2017). arXiv:1605.00903
Brandão, F.G.S.L., Harrow, A.W.: Product-state approximations to quantum ground states. In: Proceedings of the 45th Annual ACM Symposium on Theory of Computing, STOC ’13, pp. 871–880 (2013). arXiv:1310.0017
Brandão, F.G.S.L., Harrow, A.W.: Quantum de Finetti theorems under local measurements with applications. In: Proceedings of the 45th Annual ACM Symposium on Theory of Computing, STOC ’13, pp. 861–870 (2013). arXiv:1210.6367
Barrett J., Hardy L., Kent A.: No signaling and quantum key distribution. Phys. Rev. Lett. 95, 010503 (2005)
Barak, B., Kelner, J.A., Steurer, D.: Rounding sum-of-squares relaxations. In: Proceedings of the 46th Annual ACM Symposium on Theory of Computing, STOC ’14, pp. 31–40. ACM (2014). arXiv:1312.6652
Bamps C., Pironio S.: Sum-of-squares decompositions for a family of Clauser–Horne–Shimony–Holt-like inequalities and their application to self-testing. Phys. Rev. A. 91, 052111 (2015) arXiv:1504.06960
Braun, G., Pokutta, S., Roy, A.: Strong reductions for extended formulations (2016). arXiv:1512.04932
Braun, G., Pokutta, S., Zink, D.: Inapproximability of combinatorial problems via small LPs and SDPs. In: Proceedings of the Forty-Seventh Annual ACM on Symposium on Theory of Computing, STOC ’15, pp. 107–116. ACM, New York (2015)
Beigi S., Shor P.W.: Approximating the set of separable states using the positive partial transpose test. J. Math. Phys. 51(4), 042202 (2010) arXiv:0902.1806
Barak, B., Steurer, D.: Sum-of-squares proofs and the quest toward optimal algorithms (2016). arXiv:1404.5236
Blier, H., Tapp, A.: All languages in NP have very short quantum proofs. In: First International Conference on Quantum, Nano, and Micro Technologies, pp. 34–37. Los Alamitos, IEEE Computer Society (2009). arXiv:0709.0738
Boyd S., Vandenberghe L.: Convex Optimization. Cambridge University Press, Cambridge (2004)
Chefles A., Barnett S.M.: Complementarity and Cirel’son’s inequality. J. Phys. A: Math. Gen. 29(10), L237 (1996)
Chen, J., Drucker, A.: Short multi-prover quantum proofs for SAT without entangled measurements (2010). arXiv:1011.0716
Caves C.M., Fuchs C.A., Rüdiger S.: Unknown quantum states: the quantum de Finetti representation. J. Math. Phys. 43(9), 4537–4559 (2002) arXiv:quant-ph/0104088
Cirel’son B.S.: Quantum generalizations of Bell’s inequality. Lett. Math. Phys. 4(2), 93–100 (1980)
Chen, J., Ji, Z., Yu, N., Zeng, B.: Detecting consistency of overlapping quantum marginals by separability (2015). arXiv:1509.06591
Christandl M., König R., Mitchison G., Renner R.: One-and-a-half quantum de Finetti theorems. Commun. Math. Phys. 273, 473–498 (2007) arXiv:quant-ph/0602130
Chakraborty R., Mazziotti D.A.: Structure of the one-electron reduced density matrix from the generalized Pauli exclusion principle. Int. J. Quantum Chem. 115(19), 1305–1310 (2015)
Christandl M., Schuch N., Winter A.: Entanglement of the antisymmetric state. Commun. Math. Phys. 311(2), 397–422 (2012) arXiv:0910.4151
Diaconis P., Freedman D.: Finite exchangeable sequences. Ann. Probab. 8, 745–764 (1980)
Doherty, A.C., Liang, Y.-C., Toner, B., Wehner, S.: The quantum moment problem and bounds on entangled multi-prover games. In: CCC ’08, pp. 199–210 (2008). arXiv:0803.4373
Terhal B.M., DiVincenzo D.P., Leung D.W.: Quantum data hiding. IEEE Trans. Inf. Theory 48(3), 580 (2002) arXiv:quant-ph/0103098
Doherty A.C., Parrilo P.A., Spedalieri F.M.: A complete family of separability criteria. Phys. Rev. A. 69, 022308 (2003) arXiv:quant-ph/0308032
Doherty A.C., Parrilo P.A., Spedalieri F.M.: Complete family of separability criteria. Phys. Rev. A. 69, 022308 (2004) arXiv:quant-ph/0308032
Doherty, A.C., Wehner, S.: Convergence of SDP hierarchies for polynomial optimization on the hypersphere (2012). arXiv:1210.5048
Gharibian S.: Strong NP-hardness of the quantum separability problem. QIC 10(3&4), 343–360 (2010) arXiv:0810.4507
Goldreich O.: Computational Complexity: A Conceptual Perspective, 1 edn.. Cambridge University Press, New York (2008)
Grigoriev D.: Linear lower bound on degrees of Positivstellensatz calculus proofs for the parity. Theor. Comput. Sci. 259, 613–622 (2001)
Gurvits L.: Classical deterministic complexity of Edmonds’ problem and quantum entanglement (2003). arXiv:quant-ph/0303055
Horodecki M., Horodecki P., Horodecki R.: Separability of mixed states: necessary and sufficient conditions. Phys. Lett. A. 223(1–2), 1–8 (1996) arXiv:quant-ph/9605038
Helton W., McCullough S.: A positivstellensatz for non-commutative polynomials. Trans. Am. Math. Soc. 356(9), 3721–3737 (2004)
Harrow A.W., Montanaro A.: Testing product states, quantum Merlin-Arthur games and tensor optimization. J. ACM 60(1), 3–1343 (2013) arXiv:1001.0017
Harrow, A.W., Natarajan, A., Wu, X.: An improved semidefinite programming hierarchy for testing entanglement (2015). arXiv:1506.08834
Helton, J.W., Putinar, M.: Positive polynomials in scalar and matrix variables, the spectral theorem and optimization (2006). arXiv:math/0612103
Ito, T., Kobayashi, H., Matsumoto, K.: Oracularization and two-prover one-round interactive proofs against nonlocal strategies. In: Proceedings: Twenty-Fourth Annual IEEE Conference on Computational Complexity (CCC 2009), pp. 217–228 (2009). arXiv:0810.0693
Impagliazzo R., Paturi R.: On the complexity of k-SAT. J. Comput. Syst. Sci. 62(2), 367–375 (2001)
Ito, T., Vidick, T.: A multi-prover interactive proof for NEXP sound against entangled provers. In: FOCS ’12 (2012). arXiv:1207.0550
Khot, S.: On the power of unique 2-prover 1-round games. In: STOC, pp. 767–775 (2002)
Kempe J., Kobayashi H., Matsumoto K., Toner B., Vidick T.: Entangled games are hard to approximate. SIAM J. Comput. 40(3), 848–877 (2011) arXiv:0704.2903
Klyachko, A.A.: The Pauli principle and magnetism (2013). arXiv:1311.5999
Koenig R., Mitchison G.: A most compendious and facile quantum de Finetti theorem. J. Math. Phys. 50, 012105 (2009) arXiv:quant-ph/0703210
Kothari, P.K., Meka, R., Raghavendra, P.: Approximating rectangles by juntas and weakly-exponential lower bounds for LP relaxations of CSPs. In: Proceedings of the 49th Annual ACM SIGACT Symposium on Theory of Computing, pp. 590–603. ACM (2017). arXiv:1610.02704
Koenig R., Renner R.: A de Finetti representation for finite symmetric quantum states. J. Math. Phys. 46(12), 122108 (2005) arXiv:quant-ph/0410229
Lancien C.: k-extendibility of high-dimensional bipartite quantum states (2015). arXiv:1504.06459
Lasserre J.B.: Global optimization with polynomials and the problem of moments. SIAM J. Optim. 11(3), 796–817 (2001)
Laurent M.: Sums of squares, moment matrices and optimization over polynomials. Emerg. Appl. Algebraic Geom. 149, 157–270 (2009)
Liu, Y.-K.: The complexity of the consistency and N-representability problems for quantum states. Ph.D. thesis, University of California, San Diego (2007). arXiv:0712.3041
Gall F.L., Nakagawa S., Nishimura H.: On QMA protocols with two short quantum proofs. Quantum Inf. Comput. 12, 0589 (2012) arXiv:1108.4306
Lee, J.R., Raghavendra, P., Steurer, D.: Lower bounds on the size of semidefinite programming relaxations. In: Proceedings of the Forty-Seventh Annual ACM on Symposium on Theory of Computing, STOC ’15, pp. 567–576. ACM, New York (2015). arXiv:1411.6317
Masanes L.: All bipartite entangled states are useful for information processing. Phys. Rev. Lett. 96, 150501 (2006) arXiv:quant-ph/0508071
Mazziotti D.A.: Realization of quantum chemistry without wave functions through first-order semidefinite programming. Phys. Rev. Lett. 93, 213001 (2004)
Matsumoto K., Shimono T., Winter A.: Remarks on additivity of the Holevo channel capacity and of the entanglement of formation. Commun. Math. Phys. 246, 427–442 (2004) arXiv:quant-ph/0206148
Matthews, W., Wehner, S.: Finite blocklength converse bounds for quantum channels (2012). arXiv:1210.4722
Nesterov Y.: Squared functional systems and optimization problems. High Perform. Optim. 13, 405–440 (2000)
Navascues M., Owari M., Plenio M.B.: The power of symmetric extensions for entanglement detection. Phys. Rev. A 80, 052306 (2009) arXiv:0906.2731
Navascués M., Pironio S., Acin A.: A convergent hierarchy of semidefinite programs characterizing the set of quantum correlations. New J. Phys. 10(7), 073013 (2008) arXiv:0803.4290
O’Donnell, R., Wright, J., Wu, C., Zhou, Y.: Hardness of robust graph isomorphism, lasserre gaps, and asymmetry of random graphs. In: Proceedings of the Twenty-Fifth Annual ACM-SIAM Symposium on Discrete Algorithms, SODA ’14, pp. 1659–1677. SIAM (2014). arXiv:1401.2436
Palazuelos, C.: Random constructions in Bell inequalities: a survey (2015). arXiv:1502.02175
Parrilo, P.A.: Structured semidefinite programs and semialgebraic geometry methods in robustness and optimization. Technical report, MIT, 2000. Ph.D Thesis
Peres A.: Separability criterion for density matrices. Phys. Rev. Lett. 77(8), 1413–1415 (1996)
Pereszlényi, A.: Multi-prover quantum Merlin–Arthur proof systems with small gap (2012). arXiv:1205.2761
Poulin D., Hastings M.B.: Markov entropy decomposition: a variational dual for quantum belief propagation. Phys. Rev. Lett. 106(8), 80403 (2011) arXiv:1012.2050
Pironio S., Navascués M., Acín A.: Convergent relaxations of polynomial optimization problems with noncommuting variables. SIAM J. Optim. 20(5), 2157–2180 (2010) arXiv:0903.4368
Papadimitriou C.H., Yannakakis M.: Optimization, approximation, and complexity classes. J. Comput. Syst. Sci. 43, 425–440 (1991)
Rains E.M.: A semidefinite program for distillable entanglement. IEEE Trans. Inf. Theory 47(7), 2921–2933 (2001) arXiv:quant-ph/0008047
Raghavendra, P., Steurer, D., Tulsiani, M.: Reductions between expansion problems. In: CCC, pp. 64–73 (2012). arXiv:1011.2586
Mary Beth R.: Connecting n-representability to Weyl’s problem: the one-particle density matrix for N = 3 and R = 6. J. Phys. A: Math. Theor. 40(45), F961 (2007) arXiv:0706.1855
Reichardt B.W., Unger F., Vazirani U.: Classical command of quantum systems. Nature 496(7446), 456–460 (2013) arXiv:1209.0449
Reichardt, B.W., Unger, F., Vazirani, U.: A classical leash for a quantum system: command of quantum systems via rigidity of chsh games. In: Proceedings of the 4th Conference on Innovations in Theoretical Computer Science, ITCS ’13, pp. 321–322 (2013). arXiv:1209.0448
Schoenebeck, G.: Linear level Lasserre lower bounds for certain k-CSPs. In: Proceedings of the 2008 49th Annual IEEE Symposium on Foundations of Computer Science, FOCS ’08, pp. 593–602. IEEE Computer Society, Washington, DC (2008)
Shor N.Z.: An approach to obtaining global extremums in polynomial mathematical programming problems. Cybern. Syst. Anal. 23(5), 695–700 (1987)
Slofstra, W.: Tsirelson’s problem and an embedding theorem for groups arising from non-local games (2016). arXiv:1606.03140
Scholz, V.B., Werner, R.F.: Tsirelson’s problem (2008). arXiv:0812.4305
Trevisan L.: On Khot’s unique games conjecture. Bull. AMS 49(1), 91–111 (2012)
Tulsiani, Madhur: CSP gaps and reductions in the Lasserre hierarchy. In: Proceedings of the Forty-First Annual ACM Symposium on Theory of Computing, pp. 303–312. ACM (2009)
Vidick, T.: Three-player entangled XOR games are NP-hard to approximate. In: Proceedings of the 2013 IEEE 54th Annual Symposium on Foundations of Computer Science, FOCS ’13, pp. 766–775. IEEE Computer Society (2013). arXiv:1302.1242
Acknowledgement
AWH and AN were funded by NSF Grant CCF-1629809 and AWH was funded by NSF grant CCF-1452616. XW was funded by the NSF Waterman Award of Scott Aaronson. All three authors (AWH, AN, and XW) were funded by ARO contract W911NF-12-1-0486. We are grateful to an anonymous STOC reviewer for pointing out a mistake in an earlier version.
Author information
Authors and Affiliations
Corresponding author
Additional information
Communicated by M. M. Wolf
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Harrow, A.W., Natarajan, A. & Wu, X. Limitations of Semidefinite Programs for Separable States and Entangled Games. Commun. Math. Phys. 366, 423–468 (2019). https://doi.org/10.1007/s00220-019-03382-y
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00220-019-03382-y