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Teleportation and entanglement do not involve FTL communication of any kind. There is a local description of the evolution of any given quantum system in terms of its Heisenberg picture observables. The observables change only when the system changes by itself or through a local interaction with another system. Entanglement and teleportation can be ...


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You don't need to get confused with black holes. Just stand outside a train and shine a laser, and have your brother inside a train shime another laser. Your light would be traveling at speed c with respect to you. If the train was going at a speed c/2, youd conclude also that his light was going again speed 3c/2, faster than you. As @WillO implied, if you ...


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Imaginary things can "travel" faster than light A shadow or a light spot can seem to travel faster than light, because it's not a particular physical thing, but a series of separate things, separate physical particles emitted at different time and at different locations. Imagine that you have launched a lot of tiny bots into space with a very accurate ...


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I think you've said a lot of things that are correct, you've just come to the wrong conclusion. You're right that that it will take us three seconds to SEE the shadow moving across the moon, because that's how long it takes the light to get there and back. But what we'll see is not the shadow slowly moving across the moon over a period of three seconds. ...


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It is known that moving a lantern will result in a spot or projected light that travels faster than light is the screen is far enough. However, this effect and similar ones do not refer to the motion of actual objects at faster than light speeds, nor this process allows transfer of information faster than light.


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If you are happy with Bob being right only in some percentage of the cases, there is a much easier protocol which does not even require entanglement: Just let Bob guess Alice's bits. He will be right in 50% of the cases. Note that once the probability to guess the right result is above 50%, communication is possible, e.g. by doing majority voting. In fact,...



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