Schrödinger's Cat

Keeping on the cat theme, let me introduce you to Schrödinger's Cat. I am assuming your eyes glazed over and you read about four or five words of the previous post. Most people would skip it.

Ok, some guy called Schrödinger has a cat, big deal.

Ah, but Schrödinger was an evil bastard, theoretically speaking, because he devised an experiment which involved a cat, a box, deadly poison and radioactive isotope. My kinda guy! (see Bloody Cat). Anyway, back to Schrödinger's Cat and the theoretical experiment;

• place one cat into a soundproof box
• add canister of cyanide
• add radioactive-isotope-triggered release mechanism (50% chance of triggering cyanide)
• wait

Now, without opening the box, is the cat alive or dead?

This is what's called a closed quantum system. One where every possibility exists. So the cat is either alive, dead, or both.

Once measured (the box opened), then a definite state exists, so the cat is either alive, or it is dead. Prior to that, the box is said to be 'superpositioned', meaning that all conceivable options are still in existence, so the cat may be both alive and dead.

Quantum mechanics in action.