Abstract
Many proposed quantum mechanical models of black holes include highly non-local interactions. The time required for thermalization to occur in such models should reflect the relaxation times associated with classical black holes in general relativity. Moreover, the time required for a particularly strong form of thermalization to occur, sometimes known as scrambling, determines the time scale on which black holes should start to release information. It has been conjectured that black holes scramble in a time logarithmic in their entropy, and that no system in nature can scramble faster. In this article, we address the conjecture from two directions. First, we exhibit two examples of systems that do indeed scramble in logarithmic time: Brownian quantum circuits and the antiferromagnetic Ising model on a sparse random graph. Unfortunately, both fail to be truly ideal fast scramblers for reasons we discuss. Second, we use Lieb-Robinson techniques to prove a logarithmic lower bound on the scrambling time of systems with finite norm terms in their Hamiltonian. The bound holds in spite of any nonlocal structure in the Hamiltonian, which might permit every degree of freedom to interact directly with every other one.
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References
L. Susskind, Some speculations about black hole entropy in string theory, hep-th/9309145 [INSPIRE].
A. Sen, Extremal black holes and elementary string states, Mod. Phys. Lett. A 10 (1995) 2081 [hep-th/9504147] [INSPIRE].
A. Strominger and C. Vafa, Microscopic origin of the Bekenstein-Hawking entropy, Phys. Lett. B 379 (1996) 99 [hep-th/9601029] [INSPIRE].
C.G. Callan and J.M. Maldacena, D-brane approach to black hole quantum mechanics, Nucl. Phys. B 472 (1996) 591 [hep-th/9602043] [INSPIRE].
S.R. Das and S.D. Mathur, Excitations of D strings, entropy and duality, Phys. Lett. B 375 (1996)103 [hep-th/9601152] [INSPIRE].
J.M. Maldacena and L. Susskind, D-branes and fat black holes, Nucl. Phys. B 475 (1996) 679 [hep-th/9604042] [INSPIRE].
G.T. Horowitz and J. Polchinski, A correspondence principle for black holes and strings, Phys. Rev. D 55 (1997) 6189 [hep-th/9612146] [INSPIRE].
T. Banks, W. Fischler, S. Shenker and L. Susskind, M theory as a matrix model: a conjecture, Phys. Rev. D 55 (1997) 5112 [hep-th/9610043] [INSPIRE].
J.M. Maldacena, The large-N limit of superconformal field theories and supergravity, Adv. Theor. Math. Phys. 2 (1998) 231 [Int. J. Theor. Phys. 38 (1999) 1113] [hep-th/9711200] [INSPIRE].
J.M. Maldacena, Eternal black holes in anti-de Sitter, JHEP 04 (2003) 021 [hep-th/0106112] [INSPIRE].
V. Balasubramanian and B. Czech, Quantitative approaches to information recovery from black holes, Class. Quant. Grav. 28 (2011) 163001 [arXiv:1102.3566] [INSPIRE].
D.N. Page, Average entropy of a subsystem, Phys. Rev. Lett. 71 (1993) 1291 [gr-qc/9305007] [INSPIRE].
D.N. Page, Black hole information, in Proceedings of the 5th Canadian conference on general relativity and relativistic astrophysics, R.B. Mann and R.G. McLenaghan eds., (1993) [hep-th/9305040] [INSPIRE].
L. Susskind, L. Thorlacius and J. Uglum, The stretched horizon and black hole complementarity, Phys. Rev. D 48 (1993) 3743 [hep-th/9306069] [INSPIRE].
P. Hayden and J. Preskill, Black holes as mirrors: quantum information in random subsystems, JHEP 09 (2007) 120 [arXiv:0708.4025] [INSPIRE].
Y. Kiem, H.L. Verlinde and E.P. Verlinde, Black hole horizons and complementarity, Phys. Rev. D 52 (1995) 7053 [hep-th/9502074] [INSPIRE].
D.A. Lowe, J. Polchinski, L. Susskind, L. Thorlacius and J. Uglum, Black hole complementarity versus locality, Phys. Rev. D 52 (1995) 6997 [hep-th/9506138] [INSPIRE].
Y. Sekino and L. Susskind, Fast scramblers, JHEP 10 (2008) 065 [arXiv:0808.2096] [INSPIRE].
L. Susskind, Addendum to fast scramblers, arXiv:1101.6048 [INSPIRE].
C. Dankert, R. Cleve, J. Emerson and E. Livine, Exact and approximate unitary 2-designs and their application to fidelity estimation, Phys. Rev. A 80 (2009) 012304 [quant-ph/0606161].
J. Emerson, E. Livine and S. Lloyd, Convergence conditions for random quantum circuits, Phys. Rev. A 72 (2005) 060302 [quant-ph/0503210].
A.W. Harrow and R.A. Low, Random quantum circuits are approximate 2-designs, Commun. Math. Phys. 291 (2009) 257 [arXiv:0802.1919].
L. Arnaud and D. Braun, Efficiency of producing random unitary matrices with quantum circuits, Phys. Rev. A 78 (2008) 062329 [arXiv:0807.0775].
W.G. Brown and L. Viola, Convergence rates for arbitrary statistical moments of random quantum circuits, Phys. Rev. Lett. 104 (2010) 250501 [arXiv:0910.0913].
I.T. Diniz and D. Jonathan, Comment on the paper “random quantum circuits are approximate 2-designs”, Commun. Math. Phys. 304 (2011) 281 [arXiv:1006.4202].
E. Lieb and D. Robinson, The finite group velocity of quantum spin systems, Commun. Math. Phys. 28 (1972) 251 [INSPIRE].
B. Nachtergaele and R. Sims, Lieb-Robinson bounds and the exponential clustering theorem, Commun. Math. Phys. 265 (2006) 119 [math-ph/0506030].
M.B. Hastings and T. Koma, Spectral gap and exponential decay of correlations, Commun. Math. Phys. 265 (2006) 781 [math-ph/0507008] [INSPIRE].
C. Asplund, D. Berenstein and D. Trancanelli, Evidence for fast thermalization in the plane-wave matrix model, Phys. Rev. Lett. 107 (2011) 171602 [arXiv:1104.5469] [INSPIRE].
J.L. Barbon and J.M. Magan, Chaotic fast scrambling at black holes, Phys. Rev. D 84 (2011) 106012 [arXiv:1105.2581] [INSPIRE].
K. Schoutens, H.L. Verlinde and E.P. Verlinde, Quantum black hole evaporation, Phys. Rev. D 48 (1993) 2670 [hep-th/9304128] [INSPIRE].
J. von Neumann, Proof of the ergodic theorem and the H-theorem in quantum mechanics, Eur. Phys. J. H 35 (2010) 201 [Z. Phys. 57 (1929) 30] [arXiv:1003.2133].
J. Gemmer, M. Michel and G. Mahler, Quantum thermodynamics — emergence of thermodynamic behavior within composite quantum systems, second edition, Lect. Notes Phys. 784, Springer-Verlag, Berlin Germany (2009).
N. Linden, S. Popescu, A.J. Short and A. Winter, Quantum mechanical evolution towards thermal equilibrium, Phys. Rev. E 79 (2009) 061103 [arXiv:0812.2385].
S. Goldstein, J.L. Lebowitz, R. Tumulka and N. Zanghì, Canonical typicality, Phys. Rev. Lett. 96 (2006) 050403.
S. Popescu, A.J. Short and A. Winter, The foundations of statistical mechanics from entanglement: individual states vs. averages, Nature Phys. 2 (2006) 754 [quant-ph/0511225].
P. Reimann, Foundation of statistical mechanics under experimentally realistic conditions, Phys. Rev. Lett. 101 (2008) 190403 [INSPIRE].
P. Bocchieri and A. Loinger, Ergodic foundation of quantum statistical mechanics, Phys. Rev. 114 (1959)948.
S. Lloyd, Black holes, demons, and the loss of coherence, Ph.D. thesis, Rockefeller University, New York U.S.A. (1988).
H. Tasaki, From quantum dynamics to the canonical distribution: general picture and a rigorous example, Phys. Rev. Lett. 80 (1998) 1373.
P. Calabrese and J.L. Cardy, Time-dependence of correlation functions following a quantum quench, Phys. Rev. Lett. 96 (2006) 136801 [cond-mat/0601225] [INSPIRE].
J. M. Deutsch, Quantum statistical mechanics in a closed system, Phys. Rev. A 43 (1991) 2046.
M. Srednicki, Chaos and quantum thermalization, Phys. Rev. E 50 (1994) 888 [cond-mat/9403051].
A. Riera, C. Gogolin and J. Eisert, Thermalization in nature and on a quantum computer, Phys. Rev. Lett. 108 (2012) 080402 [arXiv:1102.2389].
M. Rigol and M. Srednicki, Alternatives to eigenstate thermalization, Phys. Rev. Lett. 108 (2012)110601 [arXiv:1108.0928].
M.A. Nielsen and I.L. Chuang, Quantum computation and quantum information, Cambridge University Press, Cambridge U.K. (2000).
M. Fannes, A continuity property of the entropy density for spin lattice systems, Commun. Math. Phys. 31 (1973) 291.
I. Karatzas and S.E. Shreve, Brownian motion and stochastic calculus, Springer, Germany (1991).
L. Arnold, Stochastic differential equations: theory and applications, Dover, New York U.S.A. (1974).
R. Raussendorf, D.E. Browne and H.J. Briegel, Measurement-based quantum computation on cluster states, Phys. Rev. A 68 (2003) 022312 [quant-ph/0301052].
M. van den Nest, A. Miyake, W. Dür and H.J. Briegel, Universal resources for measurement-based quantum computation, Phys. Rev. Lett. 97 (2006) 150504 [quant-ph/0604010].
M. Hein, J. Eisert and H.J. Briegel, Multiparty entanglement in graph states, Phys. Rev. A 69 (2004) 062311 [quant-ph/0307130].
V.F. Kolchin, Random graphs, Cambridge University Press, Cambridge U.K. (1999).
M. Hastings, Lieb-Schultz-Mattis in higher dimensions, Phys. Rev. B 69 (2004) 104431 [cond-mat/0305505] [INSPIRE].
P. Hayden and A. Winter, The fidelity alternative and quantum identification, arXiv:1003.4994.
P. Hayden, M. Horodecki, J. Yard and A. Winter, A decoupling approach to the quantum capacity, Open Syst. Inf. Dyn. 15 (2008) 7 [quant-ph/0702005].
B. Nachtergaele, H. Raz, B. Schlein and R. Sims, Lieb-Robinson bounds for harmonic and anharmonic lattice systems, Commun. Math. Phys. 286 (2009) 1073 [arXiv:0712.3820].
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ArXiv ePrint: 1111.6580
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Lashkari, N., Stanford, D., Hastings, M. et al. Towards the fast scrambling conjecture. J. High Energ. Phys. 2013, 22 (2013). https://doi.org/10.1007/JHEP04(2013)022
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DOI: https://doi.org/10.1007/JHEP04(2013)022