Suppose I have two cards, A and B, that I shuffle and then blindly place in two spaceships, pointed at opposite ends of the galaxy. If they go quickly enough, it can be the case that they get far enough apart that they will never be able to meet again. But if you’re in one of the spaceships, and turn the card over to learn that it’s card A, then you learn something about the world on the other side of the light cone boundary.
Suppose I have two cards, A and B, that I shuffle and then blindly place in two spaceships, pointed at opposite ends of the galaxy. If they go quickly enough, it can be the case that they get far enough apart that they will never be able to meet again. But if you’re in one of the spaceships, and turn the card over to learn that it’s card A, then you learn something about the world on the other side of the light cone boundary.