I lack the fundamental aspect of quantum entanglement and I am trying to fully understand it. The problem I have is that I can regurgitate all the information I have read however what I am saying does not make sense in my head. Schrödinger's cat for example: is entanglement completely dependent on the observer? Lets say I open the box and find the cat deceased. I then close the box and tell nobody of what I saw. I have not altered state of the cat by looking. I simply made its state known to myself. So does entanglement still exist for any other observer wanting to know the state of the cat? Expand that out to another entangled property like electron spin, how does observer B lose entanglement simply because observer A saw that his spin was up and inferred that observer B's spin must be down.