A nonsensical experiment suggested due to an equally nonsensical theory namely Quantum Mechanics. In this experiment a cute kitty cat is enclosed in a box containing say a sealed jar of a poisonous gas. boooo...
The trigger for the release of the gas inside the box is the decay of some radioactive atom. If the radioactive atom decays it sets of a hammer like action which breaks the jar containing the gas which instantly kills the cat but if it doesn't decay the cat stays alive and kicking. If the half life of the radioactive atom chosen as a trigger is say one hour then for that one hour according to laws of Quantum Mechanics the cat is neither alive nor dead but is in some sort of a superposition of both the states. Bizzare?? Definitely.
So it all boils down as to what is the true nature of radioactive decay. Is it spontaneous or not. To this day radioactivity is considered a random process. Though I believe that this is incorrect.
This was only a thought experiment devised by Erwin Schrodinger in 1935 to show the incompleteness and bizarreness of Quantum Mechanics.
I repeat no live cats were used for the Schrodinger's cat experiment you cat lovers. meow