The latest episode of Person of Interest talks about a missing character on the show in terms of Schrodinger’s cat.
Schrödinger wrote in his famous 1935 paper, Schrödinger, E. “The present status of quantum mechanics.” Die Naturwissenschaften 23.48 (1935): 1-26 about a thought experiment, in which a cat is put in a box with a lethal radioactive poison. The poison is just weak enough to ensure a 50/50 chance of survival. However, there is no way to actually know the fate of the cat without opening the box. According to quantum mechanics, the cat is in a superposition until the observation is made. Once the observation is made, classical mechanics of nature hits and the cat is either dead or alive but not both.
Since the character’s fate is not known and she’s probably in captivity of someone dangerous, root explains, that until we make an observation of actually finding her, she is neither dead nor alive but both.