D. Ranard: "Ehrenfest's theorem beyond the Ehrenfest time" (MIT)

I will discuss some basic quantum mechanics: how the classical equation of motion arises at small hbar, or large action. The classical equations can actually break down after a short time (the "Ehrenfest time"), due to chaos. We prove a general result that even weak interactions with a bath will restore the classical equations of motion (arXiv:2307.05326). The result is for systems with finite DOF, but as a discussion topic, I hope to explore these ideas in field theory.