Though 'no cloning theorem' disputed the concept of cloning, it is predicted that cloning will help to signal faster than light.
We don't have signal faster than light. But in quantum optics we have the group velocity more than light speed, It's called superluminal. You can study about that at: Enhanced effects of subluminal and superluminal propagation (Physics Letters A 327 (2004) 15–20)
The only theoretical way to harvest information faster than light would be to harness Bell's inequality - i.e. create a coherent entanglement between specific entities and engineer a way that Bell's results would be made to work in a usable way ......so that an event impacting one entity would be immediately reflected in the other, 'mate' entity's behaviour. Easier said than done ....
Assume Alice and Bob share an entangled spin state (|00> + |11>)/2^(1/2). Alice makes a measurement in some basis and obtaines one of two outcomes in that basis. There are infinite number of measurement bases and only two possible outcomes for every basis. Assume that these two outcomes will correspond to the same information, i.e. information is associated with the measurement basis, not with the measurement outcome. After the measurement the Bob's spin will be in the same state as the Alice' spin. If Bob can clone this state he can make many measurements and recover the state. If he knows the state he knows the Alice' measurement basis. In this way information could be transferred with any speed.
It’s not possible, because no such unitary operator exists. But, even were it possible, cloning doedn’t have anything to do with the speed any object can travel.
The fact that it is possible to clone classical states doedn’t have anything to do with relativity. It’s possible to copy the states of the classical electromagnetic field, judt like it’s possible to copy the states of particles.
Non-relativistic quantum mechanics describes more states than non-relativistic classical mechanics, but, in neither does the speed of light play a special role. Just like the response of rigid bodies isn’t consistent with special relativity, so are properties of entangled states. So what? The appropriate relativistic formulation in both cases is known.
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