Quantum Information Processing

, Volume 1, Issue 1–2, pp 35–43 | Cite as

An Example of the Difference Between Quantum and Classical Random Walks

  • Andrew M. Childs
  • Edward Farhi
  • Sam Gutmann


In 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

quantum random walk hitting times 


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Copyright information

© Plenum Publishing Corporation 2002

Authors and Affiliations

  • Andrew M. Childs
    • 1
  • Edward Farhi
    • 1
  • Sam Gutmann
    • 2
  1. 1.Center for Theoretical PhysicsMassachusetts Institute of TechnologyCambridge
  2. 2.Department of MathematicsNortheastern UniversityBoston

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