Fig. 1: Schematic illustration.
From: Experimental exchange of grins between quantum Cheshire cats
A non-contacting grin exchange takes place between two quantum Cheshire cats. The cats Anna with sunglasses and Belle without sunglasses independently enter two bilayer channels, where the sundered grins from the cats can be revealed by their weak values. The structure of the channels is twisted so the two paths for Anna and Belle denoted by u and the two denoted by d ultimately join each other, respectively. Consequently, after exiting the setup, both cats are astonished to find that they have swapped grins without having met each other.
