An Example of the Difference Between Quantum and Classical Random Walks

  title={An Example of the Difference Between Quantum and Classical Random Walks},
  author={Andrew M. Childs and E. Farhi and S. Gutmann},
  journal={Quantum Information Processing},
AbstractIn this note, we discuss a general definition of quantum random walks on graphs and illustrate with a simple graph the possibility of very different behavior between a classical random walk and its quantum analog. In this graph, propagation between a particular pair of nodes is exponentially faster in the quantum case. PACS: 03.67.Hk 
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