|
This is certainly interesting, however it's not going to allow faster-than-light communication. I'll try to explain.
At each (physical) end of the experiment, what each experimenter (call them A and B) sees is a particle, with the two possible states (call them Up and Down), which he measures and unpredictably comes up with one of those two states. Entanglement means that if experimenter A sees 'Up', then experimenter B must see 'Down'. So it looks like, when experimenter A performs his measurement, the information about which state he has measured is 'instantly' (faster than light) communicated to the other particle.
The problem, however, is that what experimenter A measures is random, so until he has measured the state, he doesn't know whether it will be Up or Down. Similarly, experimenter B also doesn't know whether his particle will be Up or Down until he measures it.
The only way experimenter B would know his particle's state in advance of measuring it himself, is if experimenter A sent him a message about the state of the other particle. But experimenter A can only send that message at the speed of light (since this is no longer being communicated via entanglement).
So, in fact entanglement doesn't actually communicate anything in a way that violates relativity. Prior to a 'classical' message arriving, each experimenter simply sees an unknown state particle, measures it and gets a random result.
|