On the Relation Between Quantum Computational Speedup and Retrocausality

@article{Castagnoli2016OnTR,
  title={On the Relation Between Quantum Computational Speedup and Retrocausality},
  author={Giuseppe Castagnoli},
  journal={Quanta},
  year={2016},
  volume={5},
  pages={34-52}
}
We investigate the reason for the quantum speedup (quantum algorithms require fewer computation steps than their classical counterparts). We extend the representation of the quantum algorithm to the process of setting the problem, namely choosing the function computed by the black box. The initial measurement selects a setting at random, Bob (the problem setter) unitarily changes it into the desired one. With reference to the observer dependent quantum states of relational quantum mechanics… 

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