On the Relationship Between Continuous- and Discrete-Time Quantum Walk

@article{Childs2010OnTR,
  title={On the Relationship Between Continuous- and Discrete-Time Quantum Walk},
  author={Andrew M. Childs},
  journal={Communications in Mathematical Physics},
  year={2010},
  volume={294},
  pages={581-603}
}
  • Andrew M. Childs
  • Published 1 October 2008
  • Mathematics
  • Communications in Mathematical Physics
Quantum walk is one of the main tools for quantum algorithms. Defined by analogy to classical random walk, a quantum walk is a time-homogeneous quantum process on a graph. Both random and quantum walks can be defined either in continuous or discrete time. But whereas a continuous-time random walk can be obtained as the limit of a sequence of discrete-time random walks, the two types of quantum walk appear fundamentally different, owing to the need for extra degrees of freedom in the discrete… 
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