Instantons and the quantum bound to chaos

Vijay Ganesh Sadhasivam, Lars Meuser, David R. Reichman +1

We investigate why the Lyapunov exponents $\lambda$ of out-of-time-ordered correlators (OTOCs) satisfy a universal bound $\lambda <2\pi k_{B}T/\hslash$ by probing imaginary-time path-integral spa…