Understanding Quantum Algorithms via Query Complexity

@article{Ambainis2017UnderstandingQA,
  title={Understanding Quantum Algorithms via Query Complexity},
  author={Andris Ambainis},
  journal={ArXiv},
  year={2017},
  volume={abs/1712.06349}
}
  • A. Ambainis
  • Published 18 December 2017
  • Computer Science
  • ArXiv
Query complexity is a model of computation in which we have to compute a function $f(x_1, \ldots, x_N)$ of variables $x_i$ which can be accessed via queries. The complexity of an algorithm is measured by the number of queries that it makes. Query complexity is widely used for studying quantum algorithms, for two reasons. First, it includes many of the known quantum algorithms (including Grover's quantum search and a key subroutine of Shor's factoring algorithm). Second, one can prove lower… 

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