Scrambling and the Anti butterfly effect

Complex dynamics spread local quantum information over the entire system -- a process known as scrambling. If the dynamcs is reversed, the system will be unscrambled to the initial state. The composed process "scrambling + perturbation + unscrambling" can magnify the perturbation, exhibiting the butterfly effect. This process is known as the quantum twirling channel and lies in the core of various diagnostics for quantum chaos. In this talk, we show that, through the twirling channel, part of the information damaged by certain types of perturbations can be recovered -- the anti-butterfly effect.<gdiv></gdiv>