Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: George McBean on 09/06/2010 04:30:02

Title: Can we use quantum entanglement as a means of communication?
Post by: George McBean on 09/06/2010 04:30:02

George McBean  asked the Naked Scientists:
   
I'd like to ask is it possible in theory to use quantum entanglement as a means of communication, and if it was theoretically possible, could you not then take one half of your communication device (which is linked through quantum entanglement to the other) on a space craft then fly close to the speed of light to go into the future, there by setting up a means of communication forward and backwards through time?

I expect the answer is no, but I'd like to hear an explanation of this.

Thanks

George

What do you think?

Title: Can we use quantum entanglement as a means of communication?
Post by: graham.d on 09/06/2010 15:36:22

The main question would be does Quantum Entanglement allow FTL communications. The answer is no even though you have what Einstein called "Spooky action at a distance". The problem is that you don't know the state of your half of the entangled pair until you look at it. When you look you will resolve it, and its partner, but in a random way. Your distant companion would have no way of knowning whether it was his viewing of the state of his half causing a resolution, or your actions, and both of you will see a random set of results, allbeit opposite.

This site:

http://everything2.com/title/Quantum+entanglement+and+faster+than+light+communication

gives a more comprehensive and mathematical view. There may be better ones on the web but this is the first I came across.