# Student is puzzled by quantum entanglement

I have been posting answers on some forum and they get deleted, so I will start writing short blogs with my answers to some questions.

Here is a link to a question asked by many thoughtful students when they encounter quantum entanglement. As I read the answers given, and the threads that evolved, I realized that there is a lot of confusion about this. The answers seem to wander all over the place. The question is simple

Kiss: http://en.wikipedia.org/wiki/KISS_principle

Here is his question:

HOW do we know the other particle “magically assumes” the opposite state, rather than it just had the opposite state all the time?

The answer is “nobody knows because it makes no physical sense”. When a physicist is asked how this happens, they indeed invoke the word “magic” as in quantum magic or quantum weirdness. Google them.

First using the KISS principle, entanglement arises because when we write down an equation we must label the particles, making them distinguishable. Nature does not need such labels and so particles are indistinguishable, like two electrons. Therefore to satisfy the Spin Statistics Theorem (Pauli Exclusion Principle) the singlet state, and others, must be entangled.

So you can conclude that entanglement is a property of quantum mechanics, but not of Nature.

As to how the other particle “magically assumes” the opposite state, again using the KISS or Occam’s razor principles, the only way is that they are correlated by their common origin. The student assumed this must be the case. This, however, appears to fly in the face of Bell’s Theorem, which is why physicist so far capitulate into “quantum weirdness”