  We review our recent work [arXiv:2009.10759] where we studied the chaotic
property of the two coupled Sachdev-Ye-Kitaev systems exhibiting a Hawking-Page
like phase transition. By computing the out-of-time-ordered correlator in the
large N limit by using the bilocal field formalism, we found that the chaos
exponent of this model shows a discontinuous fall-off at the phase transition
temperature. Hence in this model the Hawking-Page like transition is correlated
with a transition in chaoticity, as expected from the relation between a black
hole geometry and the chaotic behavior in the dual field theory.
