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mix609
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my question is about the no-communication theorem in quantum mechanics:
Assume that i have a pair of entangled photons which are entangled on their polarization. also assume that i send one to alice and another to bob. and alice wants to send a message to bob. no communication theorem states that communication is not possible because the polarization when measured by the sender(alice) will be random and while alice can know what result bob will get if he measures the polarization of his photon, it does not imply communication because alice would have to use a classical channel to communicate what result she got upon measurement, to bob. that defeats the very purpose of the experiment
my question is, what if its possible to control the polarization on alice's side by some means(assuming physicists find out some new novel way to do this 5 or 10 years from now. i know this is a very BIG assumption but perhaps possible after a decade more of QM research). can the no communication theorem be said to be violated now? my other question is: even if it were possible to control the polarization, would it be possible to reuse the photon pairs for communicating more than once?(cause any attempt to measure the entanglement will also destroy it. hence only 1 bit of data can be sent and the entanglement is subsequently and immediately destroyed). so can it be said that: not only is the randomness a problem, the other problem is that the entanglement can be used only once per photon pair and in order to communicate 1 byte(1 byte=8 bits) of data, one would require 8 entangled photon pairs?
Assume that i have a pair of entangled photons which are entangled on their polarization. also assume that i send one to alice and another to bob. and alice wants to send a message to bob. no communication theorem states that communication is not possible because the polarization when measured by the sender(alice) will be random and while alice can know what result bob will get if he measures the polarization of his photon, it does not imply communication because alice would have to use a classical channel to communicate what result she got upon measurement, to bob. that defeats the very purpose of the experiment
my question is, what if its possible to control the polarization on alice's side by some means(assuming physicists find out some new novel way to do this 5 or 10 years from now. i know this is a very BIG assumption but perhaps possible after a decade more of QM research). can the no communication theorem be said to be violated now? my other question is: even if it were possible to control the polarization, would it be possible to reuse the photon pairs for communicating more than once?(cause any attempt to measure the entanglement will also destroy it. hence only 1 bit of data can be sent and the entanglement is subsequently and immediately destroyed). so can it be said that: not only is the randomness a problem, the other problem is that the entanglement can be used only once per photon pair and in order to communicate 1 byte(1 byte=8 bits) of data, one would require 8 entangled photon pairs?