> why are we sure that we're not just reading off a random number generator that's set from the same seed? We aren't. In fact, according to the decoherence / m

> why are we sure that we're not just reading off a random number generator that's set from the same seed? We aren't. In fact, according to the decoherence / many-world interpretation (and possibly others) that's exactly what happens. When you "measure" (aka. entangle yourself with) one of the two photons, you end up (find yourself) in one of the infinitely many possible "worlds", in which both photons have a single, definite state (always the opposite of each other, in this setup.) It's as simple as that. I keep recommending this sequence of blog posts as the best introduction to the topic: http://lesswrong.com/lw/r5/the_quantum_physics_sequence/ http://lesswrong.com/lw/r5/the_quantum_physics_sequence/