2018 Volume 73 Issue 8 Pages 569-574
We introduce the Sachdev–Ye–Kitaev (SYK) model, which was introduced in a condensed matter theoretical context but has quickly drawn attention as one of the candidate theories for the non-gravity side of the holography principle, also known as the gauge/gravity duality. The model is known to satisfy the chaos bound of the Lyapunov exponent as in the case of certain black holes. We then review the holography principle and the SYK model and introduce the out-of-time order correlator (OTOC), which reveals the Lyapunov exponent of a quantum chaotic system. Finally, we explain our proposal for the experimental realization of the SYK model using cold atoms and molecules in an optical lattice in a way that OTOC is measurable. Experimental realization of theories that define quantum gravity would pave the way to the experimental study of quantum gravity, where condensed matter theorists and cold atom experimentalists can contribute.