If entangled particles instantly effect their partners, (i.e. if one is observed spinning one way, the other will be spinning in the opposite direction), then would that mean theoretically that quantum computers could communicate over a distance without an internet connection?

If entangled particles instantly effect their partners, (i.e. if one is observed spinning one way, the other will be spinning in the opposite direction), then would that mean theoretically that quantum computers could communicate over a distance without an internet connection?

 

 

There has to be a communication channel to send the information about how to do the measurement. You could do it by snail mail or drone courier, though, if you can keep the system from decohering for that long. You also have to get the entangled particle there, or teleport the information.

If entangled particles instantly effect their partners, (i.e. if one is observed spinning one way, the other will be spinning in the opposite direction), then would that mean theoretically that quantum computers could communicate over a distance without an internet connection?

You need a detector to detect the state by superluminal communication. How else can you make sense of the information?

There is no superluminal communication.

There is no superluminal communication.

 

Bell's theorem ??

 

Bell's theorem ??

 

That shows that there cannot be a local hidden variable which would reproduce the results we get from Quantum Mechanics. But there is nothing that makes us think that entanglement allows superluminal communication. By communication we mean the transmission of information of any sort. What happens when one of two particles which are entangled into sharing a state of superposition is measured is not communication - the effect is not local but no new knowledge is gleaned, nor is information transmitted

 

That shows that there cannot be a local hidden variable which would reproduce the results we get from Quantum Mechanics. But there is nothing that makes us think that entanglement allows superluminal communication. By communication we mean the transmission of information of any sort. What happens when one of two particles which are entangled into sharing a state of superposition is measured is not communication - the effect is not local but no new knowledge is gleaned, nor is information transmitted

 

Can such a state be non-causal ? Then it would definitely fail in some circumstances.