Schrödinger's Cat

Schrödinger's Cat is a thought experiment. You take an ordinary cat, and stick it ina box. you can't see into the box, and the cat can't get out; it's sealed. With this cat, into the box, goes a chemical. There's a 50% chance it'll react with something else in there and the cat will die. Except, a yu can't see in, you have no way of knowing which happens. According to quantum theory, after an hour the cat is in a quantom superposition of coexisting alive and dead states. Yet when we look in the box we only see one of the states, not a mixture of them. Basically, the cat is both dead and alive.

[Note, this experiment is not actually done. It is a THOUGHT experiment :)]