Can someone please explain Schrodinger and his cat without sounding like a scholar?

Question

Wikipedia doesn't make sense!

THE WORLD IS GOING TO END! RUN, THE APOCALYPSE IS COMING!

....

Yeah. It doesn't make sense. Any takers?

Answer 1

Hmm, well I don't really understand it either. But from what I gathered, this guy thought out an experiment (he never actually did it) which meant putting a cat in a radioactive proof chamber with an atom. There was a 50/50 chance the atom would decay. If it decayed, it would cause a hammer to smash a glass box full of a poisonous gas, if not, when the chamber was opened after 10 minutes or something, the cat would still be alive. The bit I don't understand is that he said the cat could hypothetically be alive and dead at the same time, so I can't help there :\ I hope this was a little bit useful.

Answer 2

An object is either dead or alive. There's no other way for it to be. In order to find out exactly what state it's in, we have to observe it. After observing it, then we can decide if it is in fact dead or alive.

Answer 3

It doesn't change the state, it somehow at the instant of observing causes the probability that the cat is alive to be 0 and to be dead becomes 1. Until that point it is 50-50 either way.

It it supposed to illustrate what they think happens - or doesn't happen. If there is a probability that something has happened, in this case that the cat has died, then the cat exists in a sort of probabilistic limbo - neither dead nor alive - until observed. Now why they use a cat I don't know since I believe a cat is quite capable of determining whether or not it is dead. It is supposed to be the act of observing that causes probabilities to be resolved and until they are things as we know them simply do not exist. Apply this to the universe. If nothing is ever observed does anything as we know things - stars, planets, etc - exist as anything more than just some sort of quantum smoke and mirrors?

Which leads to another question. Why should we ever be allowed to observe anything in the first place? And how does this observing thing work anyway if the cat isn't really dead or alive?

Answer 4

The first thing to understand is that Schrodinger's Cat is just one interpretation of Quantum Mechanics, namely the Copenhagen interpretation.

An object, such as a cat, can be alive, or it can be dead. These are two states. But in quantum mechanics, we say that until the object is observed, it is in a sum of all possible states, and then when the object is observed, it 'becomes' one of those states. So when we open the box and look at the cat, it will become either dead or alive - you need an observer to cause the object to become in a certain state.

You will never open the box to find it dead AND alive, this is something it can only be before it is observed.

Like I said, this is is only one interpretation of QM, and not a very popular one anymore. Some people believe that although it may well be impossible to know what state the cat is in without looking, it is in fact either dead, or alive.

Just to clarify something in your question, observing it after you have seen it was dead does not change it back to alive again. Only the first observation, when you did not know which state it was, will cause the cat to become either dead or alive.