entanglement?

my other thread hits on this, but i was just curious:

does anyone know much about quantum entanglement? it is my understanding that certain paired particles can interact instantaneously regardless of distance. but i have also heard that this phenomenon would be useless for faster than light communication. could someone explain to me why this is, or point me toward some reading that would?

 

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Your probably best first checking what online Encyclopedia's have: http://en.wikipedia.org/wiki/Quantum_entanglement

From there you should get an idea of what to look for: which experiments, which authors etc.

 

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I guess that this is a perfect thread for MacM,

As MacM will argue, information is transfered between the particles. However, my knowledge does not extend as far as his does in this field.
However, why would it be useless? We have a binary system, either the particle is there, or it has collapsed. On/Off, just like light.

 

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From what I understand, it is currently considered useless because of the volitility of it. Being able to get useful information across distances appears to be impossible (not sure if that is because of difficulties in encoding the information into the local half of the pair, or if the observation of the remote particle may effect the information, though)
Other people can speak better to this than my layman's understanding. Any physics majors around?

interesting links:
http://www.newscientist.com/article.ns?id=dn2796
http://physicsweb.org/articles/world/13/9/3

 

I think the reason it is useless is because you don't know which, say, spin is going to come out. particle A might know instantaneously that particle B has "chosen" to spin up, so particle A will take the opposite spin, but we cannot predict which spin B will "choose". so how can we send data? if you don't know if you are going to send a 1 or a zero, then it is pretty much pointless to even send anything.