Mentor

## Faster than light information travel

 Quote by JohnLuck A) It is not obvious to me that filtering breaks entanglement. It depends on whether the filtering interacts at all with the photons that pass through it. Do you know the properties of all types of polarization filters?
All polarization filters place the photons into an eigenstate, if they do not do that then they are not filters. Entanglement only happens when the state is a superposition of eigenstates, so it is self-contradictory to claim that you have placed a pair of photons in an entangled eigenstate.
 ... I... just... Wow. Well, good luck with breaking physics. I'm out.

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 Quote by JohnLuck B) You are wrong. Measuring the angle B would set the angle A at random for all the photons. This is what is so special about entanglement, the entangled pair affect each other instantaneously over a distance, (Einstein called it "spooky action at a distance"). I suggest you read up on it. Also what did you think entanglement was?
You are being unnecessarily rough with this comment.

The fact is that your idea does not transfer any useful information faster than light. All outcomes appear completely random regardless of the angle you select to measure, and regardless of what you do elsewhere. No pattern emerges until and unless you compare Alice's result with Bob's. That requires a traditional information channel operating no faster than c.
 (Apologies DrChinese, I just saw your response.) JohnLuck, would I be right in thinking the you want to use the machine to send information faster than light? If so, my understanding is that this is not possible. (Geogir / DrewD / DrChinese, you seem like you could you confirm / refute this ... please?) The only way to decript the "message" is to follow up with a letter / phonecall to explain to the Martian how the key to the message (which will change with every message) works. Otherwise the Martian only knows the the answer to the question is yes / no (0/1), not what the question is. And you can't agree the question in advance, because until you measure your particle, you don't know if it needs to be positive or negative. I'm no expert on this, just a reader like yourself, but I hope that this helps. Regards, Noel.

 Quote by georgir ... I... just... Wow. Well, good luck with breaking physics. I'm out.
Sorry, my reply was worded unnecessarily arrogant sounding. What I meant was something like "What is your understanding of how entanglement works?" It was not meant to be so condescending.

 Quote by DaleSpam All polarization filters place the photons into an eigenstate, if they do not do that then they are not filters. Entanglement only happens when the state is a superposition of eigenstates, so it is self-contradictory to claim that you have placed a pair of photons in an entangled eigenstate.
This is probably why it wouldn't work then! My machine would require us to only send photons with a certain spin and the receiver to know about this default spin. If there is no way to do that, then certainly there is no way to send information using this. So I guess this is solved.

Thanks for all the comments!