Chaos in a classical limit of the Sachdev-Ye-Kitaev model

We study chaos in a classical limit of the Sachdev-Ye-Kitaev (SYK) model obtained in a suitably defined large-Slimit. The low-temperature Lyapunov exponent is found to depend linearly on temperature, with a slope that is parametrically different than in the quantum case: It is proportional to N/S The classical dynamics can be understood as the rotation of an Ndimensional body with a random inertia tensor, corresponding to the random...