Editing Quantum information (section)

==== Development from atomic physics and relativity ====
In the 1970s, techniques for manipulating single-atom quantum states, such as the [[atom trap]] and the [[scanning tunneling microscope]], began to be developed, making it possible to isolate single atoms and arrange them in arrays. Prior to these developments, precise control over single quantum systems was not possible, and experiments used coarser, simultaneous control over a large number of quantum systems.<ref name="Nielsen2010" /> The development of viable single-state manipulation techniques led to increased interest in the field of quantum information and computation.

In the 1980s, interest arose in whether it might be possible to use quantum effects to disprove [[Theory of relativity|Einstein's theory of relativity]]. If it were possible to clone an unknown quantum state, it would be possible to use [[Quantum entanglement|entangled]] quantum states to transmit information faster than the speed of light, disproving Einstein's theory. However, the [[no-cloning theorem]] showed that such cloning is impossible. The theorem was one of the earliest results of quantum information theory.<ref name="Nielsen2010" />