Spatial search by quantum walk

  title={Spatial search by quantum walk},
  author={Andrew M. Childs and Jeffrey Goldstone},
  journal={Physical Review A},
Grover's quantum search algorithm provides a way to speed up combinatorial search, but is not directly applicable to searching a physical database. Nevertheless, Aaronson and Ambainis showed that a database of N items laid out in d spatial dimensions can be searched in time of order {radical}(N) for d>2, and in time of order {radical}(N) poly(log N) for d=2. We consider an alternative search algorithm based on a continuous-time quantum walk on a graph. The case of the complete graph gives the… 
Quantum Search of Spatial Regions ( Extended Abstract ) ∗
An O( √ n)-qubit communication protocol for the disjointness problem is given, which improves an upper bound of Høyer and de Wolf and matches a lower bound of Razborov.
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Quantum search of spatial regions
  • S. Aaronson, A. Ambainis
  • Computer Science
    44th Annual IEEE Symposium on Foundations of Computer Science, 2003. Proceedings.
  • 2003
An 0(/spl radic/n)-qubit communication protocol for the disjointness problem is given, which improves an upper bound of Hoyer and de Wolf and matches a lower bound of Razborov.
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