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zonde
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I would like to post a comment for offtopic conversation in another thread.
But conclusions of no-communication theorem are limited by it's assumptions (as for any no-go theorem). To illustrate this let me describe one example.
If you colocate Alice and Bob then by measuring both photons and comparing result you can see if entanglement is present or not. Now depending on physical model of entanglement it might be possible to break entanglement from distance and see it in local results of colocated Alice and Bob. Say if there is no direct photon-photon entanglement but instead photon-photon entanglement is realized by combination of electron-photon entanglements. Then the electron (at the source) can be distant from Alice/Bob pair. So in such a model if there is a way how to break electron-photon entanglement by having control of electron (and optical paths connecting electron and photons) it would open possibility for FTL communication.
This is the point of no-communication theorem that measuring one particle does not change anything measurable about the other particle.adfreeman said:It wouldn't matter if you can't know from measuring one particle whether the other is still entangled or not.
But conclusions of no-communication theorem are limited by it's assumptions (as for any no-go theorem). To illustrate this let me describe one example.
If you colocate Alice and Bob then by measuring both photons and comparing result you can see if entanglement is present or not. Now depending on physical model of entanglement it might be possible to break entanglement from distance and see it in local results of colocated Alice and Bob. Say if there is no direct photon-photon entanglement but instead photon-photon entanglement is realized by combination of electron-photon entanglements. Then the electron (at the source) can be distant from Alice/Bob pair. So in such a model if there is a way how to break electron-photon entanglement by having control of electron (and optical paths connecting electron and photons) it would open possibility for FTL communication.