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== Quantum query complexity == For bounded-error quantum query complexity, the best known lower bound is

    Ω
    
      
        (
      
    
    
      n
      
        2
        
          /
        
        3
      
    
    (
    log
    
    n
    
      )
      
        1
        
          /
        
        6
      
    
    
      
        )
      
    
  

{\displaystyle \Omega {\bigl (}n^{2/3}(\log n)^{1/6}{\bigr )}}

as observed by Andrew Yao. It is obtained by combining the randomized lower bound with the quantum adversary method. The best possible lower bound one could hope to achieve is

    Ω
    (
    n
    )
  

{\displaystyle \Omega (n)}

, unlike the classical case, due to Grover's algorithm which gives an

    O
    (
    n
    )
  

{\displaystyle O(n)}

-query algorithm for testing the monotone property of non-emptiness. Similar to the deterministic and randomized case, there are some properties which are known to have an

    Ω
    (
    n
    )
  

{\displaystyle \Omega (n)}

lower bound, for example non-emptiness (which follows from the optimality of Grover's algorithm) and the property of containing a triangle. There are some graph properties which are known to have an

    Ω
    (
    
      n
      
        3
        
          /
        
        2
      
    
    )
  

{\displaystyle \Omega (n^{3/2})}

lower bound, and even some properties with an

    Ω
    (
    
      n
      
        2
      
    
    )
  

{\displaystyle \Omega (n^{2})}

lower bound. For example, the monotone property of nonplanarity requires

    Θ
    (
    
      n
      
        3
        
          /
        
        2
      
    
    )
  

{\displaystyle \Theta (n^{3/2})}

queries, and the monotone property of containing more than half the possible number of edges (also called the majority function) requires

    Θ
    (
    
      n
      
        2
      
    
    )
  

{\displaystyle \Theta (n^{2})}

queries.

== Notes ==

== References ==

== Further reading == Bollobás, Béla (2004), "Chapter VIII. Complexity and packing", Extremal Graph Theory, New York: Dover Publications, pp. 401437, ISBN 978-0-486-43596-1. Lovász, László; Young, Neal E. (2002), "Lecture Notes on Evasiveness of Graph Properties", arXiv:cs/0205031v1 Chronaki, Catherine E (1990), A survey of Evasiveness: Lower Bounds on the Decision-Tree Complexity of Boolean Functions, CiteSeerX 10.1.1.37.1041. Michael Saks, Decision Trees: Problems and Results, Old and New (PDF)