Bioshock 2 Easter Egg - Schrodinger's Cat

In Dyonisis Park, there is a room completely filled with ice (and turrets and cameras; you even need to melt the door with Incinerate! to open it). Inside the room, melt every ice block you find with the Incinerate! plasmid. Underneath one of them is a dead cat, frozen solid. Place your cursor over it, and its name appears as Schrodinger.

This is a reference to Austrian theoretical physicist Erwin Schrodinger, famous for his 'Schrodinger's Cat' theory. The theory (roughly) states that if a cat is sealed in a box with a radioactive isotope and a poison gas mechanism, and not observed, then the cat is both alive AND dead until it is observed by another sentient being; whereupon one of the two states is determined.