For our final trip down the proverbial rabbit hole of Thought Experiments, it's time we get inside the box, in a manner of speaking. Of the countless potentials for Thought Experiments, this particular example calls for the greatest ability for mental Yoga.
Imagine, for a moment, that there is a box which is opaque. The only way to see inside is to open the lid. Inside this structure is a a vial of a highly toxic substance, generally listed as hydrocyanic acid. Next to the vial of acid is a radioactive substance. Positioned nearby is a Geiger Counter, which when it detects radiation, causes the the vial of acid to break. Topping off this peculiar set-up is a cat. Now, the Geiger Counter is on, and the lid is sealed. What happens?
Presumably, one of two outcomes: The vial is broken by the Geiger Counter (given the radiation inside the box), and the cat is killed. The only other outcome is that the Geiger Counter never registers the radiation, and the cat lives.
So, is the cat alive or dead?
The only way to know for sure is to open the box. At this point, we can determine the state of things but we cannot know anything until then.
This argument is a classic in the world of Quantum Physics known as Schrodinger's Cat. The point of the arguments is best described by Erwin Schrodinger himself.
"It is typical of these cases that an indeterminacy originally restricted to the atomic domain becomes transformed into macroscopic indeterminacy, which can then be resolved by direct observation. That prevents us from so naively accepting as valid a "blurred model" for representing reality. In itself, it would not embody anything unclear or contradictory. There is a difference between a shaky or out-of-focus photograph and a snapshot of clouds and fog banks." This experiment has been the subject of countless arguments, articles, and pieces of fiction since it was written initially in the German magazine
Naturwissenschaften in 1935.
The two most common outcomes of the Schrodinger's Cat experiment fall to the "Copenhagen Interpretation" as set forth by Niels Bohr and the "Many Worlds" model of Hugh Everett. Bohr believed that all situations were relative to observation and could thereby simply be determined by opening the box, and that no real conclusion could be drawn or theorized otherwise. Everett, on the other hand, would have argued that the conclusion was that the cat would be
both dead and alive. The "Many Worlds" view would say that the instant the box was closed, two points diverged, one in which the cat would be killed, and the other where the cat would survive the encounter. These two separate worlds would split off and go forward into their logical futures.
There have been many arguments made regarding this experiment. An earlier version of the experiment that was posed to Albert Einstein by Schrodinger replaced the acid with active gunpowder and a detonation method. Einstein's response, when addressing Schrodinger in a 1950 letter, was illustrating the point of other scientists and Schrodinger. "Most of them simply do not see what sort of risky game they are playing with reality—reality as something independent of what is experimentally established. Their interpretation is, however, refuted most elegantly by your system of radioactive atom + amplifier + charge of gunpowder + cat in a box, in which the psi-function of the system contains both the cat alive and blown to bits. Nobody really doubts that the presence or absence of the cat is something independent of the act of observation."
