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Random-matrix behavior in the energy spectrum of the Sachdev-Ye-Kitaev model and in the Lyapunov spectra of classical chaos systems Masaki Tezuka (Department of Physics, Kyoto University) SYK model [A. Kitaev: talks at KITP (Apr 7 and May 27, 2015)] = 3! 3/2 1≤<<<≤ 1. Solvable at large-N (strong coupling when βJ>>1), finite entropy / N at T0 2. Holographically corresponds to 1+1D black holes 3. Satisfies the chaos bound “Fast quantum information scrambler” (Conjectured upper bound of the Lyapunov exponent L = 2 B realized, as in black holes) J. S. Cotler, …, MT, JHEP 1705, 118 (2017) (arXiv:1611.04650)

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  • Random-matrix behaviorin the energy spectrum of the Sachdev-Ye-Kitaev model and in the Lyapunov spectra of classical chaos systems

    Masaki Tezuka(Department of Physics, Kyoto University)

    SYK model

    [A. Kitaev: talks at KITP (Apr 7 and May 27, 2015)]

    𝐻 =3!

    𝑁3/2

    1≤𝑎

  • Random-matrix behaviorin the energy spectrum of the Sachdev-Ye-Kitaev model and in the Lyapunov spectra of classical chaos systems

    Masaki Tezuka(Department of Physics, Kyoto University)

    Dip-ramp-plateau structure similar to𝑔 𝛽, 𝑡 for 𝑁 ≡ 2 mod 8

    𝐺 𝑡 = 𝜒𝑎 𝑡 𝜒𝑎 0

    𝑍 𝛽, 𝑡 = Tr e−𝛽 𝐻−i 𝐻𝑡𝑔 𝛽, 𝑡 =𝑍 𝛽, 𝑡 2 𝐽

    𝑍 𝛽 𝐽2

    ~ 𝑡1 ramp: strong rigidity

    Spectral form factor[You, Ludwig, Xu 2017]

  • Random-matrix behaviorin the energy spectrum of the Sachdev-Ye-Kitaev modeland in the Lyapunov spectra of classical chaos systems

    Masaki Tezuka(Department of Physics, Kyoto University)

    𝛿𝜙𝑖 𝑡 = 𝑇𝑖𝑗𝛿𝜙𝑗 0Deviation at t initial infinitesimal deviation

    Singular values of 𝑇𝑖𝑗: 𝑎𝑘 𝑡 𝑘=1𝐾

    Time-dependent Lyapunov spectrum

    𝜆𝑘 𝑡 =log 𝑎𝑘 𝑡

    𝑡𝑘=1,2,…,𝐾

    M. Hanada, H. Shimada, and MT,

    Phys. Rev. E 97, 022224 (2018) (arXiv:1702.06935)

    Spectral correlation in 𝜆𝑘 𝑡 observed forvarious classical chaos systems:Logistic map, Lorenz attractor, etc.

    𝐾 × 𝐾 matrix

    Width ℎ

    Random matrix product

    Ongoing workQuantum chaos systems e.g. the SYK model:

    Definition of Lyapunov spectra and study of its behavior